I recently bought Pokemon Rescue Team, and I just gained the ability to evolve my pokemon. So I'm no longer a Charmander now, but a Charizard, and my partner is a massively hulking Blastoise. Now, there's no doubt that a Charizard/Blastoise team is a lot more powerful than a Charmander/Squirtle team, but I miss my cute little compadres that I saved the world with. They're just not the same.

So, topic. Has there been anything in any video game that was completely optional, that you did anyway, but found that you regretted later? Evolving Pokemon is a prime example.