A lot of people new to CI (Continuous Integration) install VS (Visual Studio) on their CI server "because it is required to compile the code". MSTest is a common reference brought up here.
Why should I not install VS (or generally speaking, any software not out-of-the-box) on my CI server?
(This question has not been asked before apparently, so I'm adding it for reference. If it already exists, sorry, I missed it, please merge. If no answer is provided to this question within some time I can add one myself)