No, they are not worth it.
What do you get?
nothing, yet people think it validates themselves somehow.
i like the way that games like Legendary did them, usually for uncovering something, or finding something humorous, there was even a achievement to poke fun at themselves, and apologize for the achievement name "Dou-bull Trou-bull"(i forget if that's the name) and gave you an achievement named "I owe you an apology".
If they're witty, i guess have them, but if they're stock, you deserve a sledgehammer in the ear.