What is over -specification?

Over-specification is where there is too much information about what size somethign is or how do or make something.

For example a piece of rope that is to be cut in half.

Correct specification would read: Rope length 50m, cut at 20m from the left.

Over-specification would read would read: Rope length 50m, cut at 20m from the left and 30m from that right.

In this case "30m from the right" is too much and can be computed from what was said before.

It is rather dangerous because designers tend to update specification at the specific part sub part without considering the whole. This can lead to serious problem when the original updater isnt present to confirm the correct spec.

Eg Consider what would if we need 5 more meters on the left piece and someone updated the spec badly. The overspecificed version would read.

Rope length 50m, cut at 25m from the left and 30m from that right. ... which is simply not possible, and creates a problem figuring out which number was updated and which is correct.