When to stop testing or stop documenting?

As product managers, every now and then we have to make decision whether to continue testing that feature or move on? It doesn't just apply to testing efforts, but also to test case coverage & documentation, i.e. to continue writing more test cases for a particular feature or move on to next?

How do you decide in such cases?

Maybe we can borrow a concept or two from behavioural psychology: maximizing and satisficing.

‍Maximizing is when you're trying to do as much as possible within given means.

‍Strictly in psychology terms, Maximization is a style of decision-making characterized by seeking the best option through an exhaustive search through alternatives.‍

Satisfising is when you're trying to do just good enough to be satisfied (MVP for ideas and decisions).

‍In psychology terms, Satisfising is a style of decision-making which would mean exploring through options until you find one just enough or acceptable enough.

So which one to use when?

Look how often your customer spend time on this feature. If it's, say 80% - 90%, it's certainly calls for maximizer behavior - and you want to put everything you have in your arsenal at this, in terms of testing and documenting.

If the feature is occasionally used, you can get away with satisfising. You just need to do enough so that you know it works as desired - nothing more!

Obviously this principle can be applied on all types of optimization problems: at work and at life in general.