To an inexperienced eye, it would appear that the more work an engineer puts into any construction project, the better the outcome is likely to be and the better the performance as well. You would, for instance, expect that a mechanical engineer would go for bigger, complex equipment when installing, say, HVAC systems instead of going for relatively simple equipment which can still get the job done. Well, you would be absolutely wrong for thinking all that. In the world of engineering, there is indeed such a thing as doing too much.
The work of an engineer, at its very core, is to try and find or devise ways to make systems more efficient, more productive and as simple as possible. The simpler a system is, the better it is as well provided that it is able to serve the purpose for which it was intended. And that is exactly what an engineer has to do- to find the simplest yet most effective and efficient solution to a problem. Anything else will constitute what is referred to as over engineering and is totally unnecessary, not to mention the fact that it could also have far reaching ramifications at the end of the day which are explained below.
Why is over engineering the wrong way to go?
One of the biggest problems associated with over engineering is that it does nothing to improve the performance and, in the best case scenario, it only maintains the status quo. But that is only the best case scenario which is rare. What normally happens is that over engineering ends up driving the costs of the project upwards, higher than it needs to be without giving any justification for the additional costs incurred. The costs can be incurred in many different ways; first of all buying oversized components is expensive and this leads to higher material costs and the extra work involved in working with the components drives up the costs of labor eventually making the project more expensive than it has to be.
Another disadvantage of over engineering is that it complicates everything for no good purpose. The reason why simplicityis one of the goals of engineering is that it reduces the possibility of mistakes and errors. Over engineering, in the other hand, increases the complexity of systems and thereby creates more room for errors which could lead to change requests that cost both time and money in the best case scenarios.
Except in the case of electrical circuits, over engineering will usually also reduce or compromise the performance of systems. In this respect, HVAC systems are the biggest victims because while simple systems can also have challenges, over engineered systems usually tend to be more vulnerable and also more difficult to fix when problems occur. In the case of oversized electrical circuits, over engineering has one benefit in that oversized conductors tend to reduce voltage drops and heat dissipation both of which are important in terms of improving performance of the system.