Brooks's law

https://en.wikipedia.org/wiki/Brooks%27s_law:

Brooks's law is an observation about software project management according to which "adding manpower to a late software project makes it later"

Goodhart's law

https://en.wikipedia.org/wiki/Goodhart%27s_law:

'"When a measure becomes a target, it ceases to be a good measure." 

One way in which this can occur is individuals trying to anticipate the effect of a policy and then taking actions that alter its outcome.'

The "Chesterton's fence" principle

 https://en.m.wikipedia.org/wiki/G._K._Chesterton#Chesterton's_fence:

In the matter of reforming things, as distinct from deforming them, there is one plain and simple principle; a principle which will probably be called a paradox. There exists in such a case a certain institution or law; let us say, for the sake of simplicity, a fence or gate erected across a road. The more modern type of reformer goes gaily up to it and says, 'I don't see the use of this; let us clear it away.' To which the more intelligent type of reformer will do well to answer: 'If you don't see the use of it, I certainly won't let you clear it away. Go away and think. Then, when you can come back and tell me that you do see the use of it, I may allow you to destroy it.'