My understanding of the phrase 'do it well' isn't as an injunction but as a way of saying that if you restrict your program to one thing, you'll have the abilit

My understanding of the phrase 'do it well' isn't as an injunction but as a way of saying that if you restrict your program to one thing, you'll have the ability to do it very well. It's to contrast it to a program that does multiple things, not so well.