Avoid the Land of Feature Creep where the Tech Debt Lies
Funny but true story. I'm at a Ticket to Ride tournament (because I love strategy board games) and seated at a table with another person who turns out to be a programmer and we get to discussing programming philosophy, to which I cite The Art of UNIX Programming as a good read and very influential in my life.
And the other programmer, Eric, says, "Yeah, I wrote it."
Perhaps subliminally seeing his name tag, the book came to mind. I don't recall but I'm not sure it had his full name on the badge. It was the first book I read which said programs ought do one thing well.