What was the biggest mistake you've made this month?

Admitting your mistakes is just as important when continuously growing as a developer and designer.

Adopted an antiquated framework? Enabled and force pushed your changes to a team's master? Built everything with script.aculo.us?

More times than you think, it's also beneficial to your colleagues as well (whether they admit it or not), since you're sharing something that can help them improve their skill sets with intellectual feedback based on personal experience.

Well, here I am, shaking my head in disappointment. I was so happy that I had separated two database models last week, but as the "full picture" started to become much more clear to me that it was not only an unnecessary approach (since there are better ways to handle the intended goal), but also started an avalanche of changes that went against my personal love of writing DRY code. (aka , "Don't Repeat Yourself".)

I don't feel time was wasted, because now this goes into my mental log as "shit not to do", which is a fairly critical part of your evolution as a professional.

So, as a friendly counter to the question, "What was your biggest success this week?"...

What was the biggest mistake you've made this month?