Premature gear defenestrations

I'm wondering if anyone has stories of episodes when you upgraded gear only to realize that tubes or some other smaller change would scratched that itch?

These fora are chock full of comparisons between various kinds of gear -- often involving tubes or other important parts of the chain. Too often, the comparisons are apples-to-oranges because too many variables are in play.

But we sometimes neglects those variables, ourselves.

So...can you think of a time you sold a piece of gear only to realize later that you should have tried different tubes or better cables, etc.? In other words, times you didn't quite do due diligence and made a change too quickly? What happened?