Q. 104  A common technique used to streamline a process is the removal of bottlenecks or constraints. Though "bottleneck" and "constraint" may seem similar, they are actually different. Explain the difference between Bottleneck and Constraint with examples. 

 

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Constraint is a restriction of  process like policy, people, material which does not allow us to meet customer requirement on the other hand bottleneck comes due to bad management process like a resource/process that can’t keep up with the demand placed on it

 Definitions of Constraint and Bottleneck:

Constraint : It is a limitation or a restriction forced upon on something by someone or by somebody or by something.  
Bottleneck : From a business context , it can be defined as one which delays or hampers the development or progress of something.

 

When Can a bottleneck happen ?

If a constraint is bound to happen for a particular activity or thing and if there is going to be an impact to that activity/thing , then it will result in a bottleneck for that activity/thing, unless there are any other alternatives to that constraint.

Just to tell an interesting point on bottleneck  If you had observed traditionally 'Soda' or soft drink bottles (nowadays tinned cans are the order of the day :-), the top part(neck) of the bottle would be narrow. It was designed to stem the liquid gushing to the throat(to regulate the liquid flow) and with that narrow neck, it was easy for a person to drink the fluid(be it water or any soft drinks or any liquid) slowly and ensured the person took only what he/she could drink/sipping.This regulation slows or delays the flow of the liquid. Applying this in a business context, bottleneck means a delay happening on something.

Let us see some examples for constraint and bottleneck, how constraints impact bottlenecks.

Eg.1: Imagine a National Highway passes through your city. The National highways department and City administration have started constructing a bridge(fly over) and hence work has commenced in a key road. Suddenly that 200 ft road is reduced to 150 ft road as digging work for the construction , has reduced the original space. This is the case for atleast 1 km of distance. The traffic becomes jammed and this stretch alone takes 30 minutes for you to pass through everyday(assume you travel by this route to your office daily) and you cross this normally in 3 min. What do we know from this ? There is a constraint here which is 'lack of road space'. This was imposed by the National Highways Department. Whats the bottleneck here ? The bottleneck is the stretch of 1 km where the road is narrowed and as a result of which the movement of vehicles are forced to go slow.  This shows that the constraint causes the bottleneck to happen.

Eg:2  
Assume you are the team lead of an IT company. A critical project is going on. Just on the week of software delivery to the customer, your experienced human resource with relevant domain expertise(SME) is not available, whatever be the reasons. Is that not a human resource constraint? Yes it is. Will it create a bottleneck ? Yes, very much likely [unless there are other SMEs or if there is no explicit need for that SME's knowledge- but it could be still a risk ]. Why bottleneck - because it will hamper(or delay) the progress of the software delivery. So what is the constraint here ? 'Non-availability of Human Resource- Domain Expert(SME)' is the constraint and bottleneck is the unnecessary waiting time for SME to return or elapsed time/extra time (of working by other people or involvement of other SMEs) involved in this delivery process.

Eg:3
We will see a similar but slightly different one than Eg.2. Imagine you manage a software project. Your team is finalizing the project design this week. Unfortunately your technical architect has not turned up to office for 2 days. Again this would be a constraint. But whether it turns out to be a bottleneck or not , depends on how it impacts the team. If the team has sufficient technical SME knowledge or take help of other technical architects from other teams who know this project's technical architecture or find some other ways to wriggle out of this issue, then it may not cause a bottleneck. Else there would be delay in finalisation of the project design with respect to the technical architecture. 'Non availability of human Resource-Technical Expertise' is the constraint. 'Delay Involved in getting technical expertise' is the bottleneck

 

Can the impact of a constraint be prevented,eliminated,mitigated/minimised? Is that possible. In other words, can bottlenecks be avoided, eliminated, mitigated or minimised?

 

 Yes quite possible. Let us see some examples.In Film Industry, every movie has to be certified by the Film Censor Board.Censor board has to approve the movie for release and provide a rating to the movie. Unless the approval comes from the Censor Board, a.movie cannot be released.  Now this is a regulatory constraint which means this is mandatory. Normally when a movie is all set to be ready, it is sent to Censor Board for screening and getting the board's feedback and approval. The point is that in case the movie does not have any objectionable scene or language used or any other action or gesture which is seen by the board as objectionable one, then it would get cleared by the board. In such a case, there would not be any more delay in the release of the  movie. Therefore, the bottleneck(delay in release) is avoided here. In case, the movie is having objectionable scenes, languages, gestures, in the opinion of the board, then per board' s guidance , the film unit has to act and this can delay the movie release. 

 

As we had seen the impact of a constraint getting eliminated here, let us take another example for mitigating the impact of a constraint.Take the two examples related to the non-availability of two human resources- the SME and the Technical Architect. What if there were backups available for these 2 resources ? Imagine, the project teams survived the duration  (when these key folks were not available)

in a very difficult way, but managed to survive, thanks to the secondary or backup specialists (could be some experienced professionals within the team or may be pulled from some other projects within the Organisation). In this case, the effect of the constraint is mitigated. 

 

Let me give one more example for avoiding the impact of a constraint. Reconsider the road traffic example. If you know that there is a parallel alternate route to your office and that you can cover the same 1 km distance (where the bottleneck stretch is there in the national highway road) in 15 min, instead of that 30 minutes, would you not try it out? Extend this to the business world. How many times you would have come across scenarios where customers would insist certain proprietary rigid tools of theirs, alone to be used by you(as a vendor) and how many times you would have gone to use some other better tools(in whatever ways) to achieve the customer stated purpose. Note it could be other way (vendor tools not good enough) as well. [Quoting "customer" side tools, here simply because customer is the king for any business. ]. Thus, we can avoid the impact of a constraint.

 

Conclusion:

As we have seen , Constraints are limitations/restrictions placed upon on something. It can be a mandatory constraint  (regulatory/legal), project needs, situational(that could be circumstances based). Outcome of a constraint can result in a bottleneck, if there is an impact to the activity or a thing on which the constraint is applied upon. Therefore, constraint and bottlenecks are two different entities  or aspects and bottleneck is the effect of a constraint getting happened or applied. 

 

Constraint is a limiting factor to organizational performance. It is an obstacle to the organization reaching its goals.

Bottleneck reduces the speed of the process.

 

We may have multiple bottleneck but only one constraint. any process outputs depends on constraint as it is the slowest or most problematic process as well as bottleneck. In any process, there will be always both bottleneck and constraint. In any process constraint can not be eliminated but it can be controlled and segregate and all constraints are bottleneck but not vice versa. as whatever step is reducing the speed of process is bottleneck so constraint also reduces speed so all constraints are bottleneck but not vice versa.

 

For example there are two machines for production, out of which machine A has high SPM of 14 and other machine B has low SPM of 9. So while production we are seeing that there are some parts which are running on machine A, runs at low speed of 9 SPM, so it is impacting productivity and output as we are getting only 540 units instead of 840 in one hour, so a huge loss is there due to bottleneck, as part profile is different we cant run at full speed because problems can be generated at full speed for getting out parts form machine. it is bottleneck for the machine A process. But on the other side Machine B has a SPM of 9 only and its productivity is less as compared to machine A and it is constraint for the organization as it gives less output .

 

So it is problematic condition that if we runs parts of slow SPM at machine A then we have loss of productivity although our machine B is already at low SPM, so we are not able to produce as expected. So for full utilization of constraint, we shifts the parts of low spm of 9 which were running on machine A shifts on Machine B which runs at a SPM of 9, so by doing this we are utilizing both machines fully and we can get better output.

 

 So by doing this we eliminate our bottleneck and elevate our constraint as now we are taking full utilization of Machine B with low SPM parts and Machine A with high SPM parts for better productivity.

 

 

 

 

 

HI,

Difference between bottleneck & Constraint in my view

Bottle neck:

A resource with lesser capacity.

There may be multiple bottlenecks for a process or organization.

Improvising the bottleneck does not add value to the process.

Bottleneck is  not always a constraint

Constraint :

It is a limiting factor to achieve the required target.

For any process or organization only one constraint will be there.

constraint can be called as a bottleneck.

Prioritize the focus on to the constraint to achieve the results, constraint act as a gate.

 

 

 

Thanks & regards

Ajay babu M

 

Constraints defines restrictions or impossible to do that ex design or features.

But bottleneck is you are at the extreme case of your limits

R Rajesh's answer is the best answer due to the multiple examples outlined from different realms. 

 

Do read through Vastupal's answer for additional examples and Ajay's answer for a  good visual depiction.