I disagree. I loved supergirl and steel. some straight to video movies are way better,then AAA movies in my mind. I guess that makes me a hipster. 

I'm not big on superhero movies, but, the worst movie I've ever seen is watchmen.... I think that's what it was called.... boring as fuck, lame, I couldn't sit through it. I threw the dvd away. My favorite? Avengers. Fucking great movie.

If it counts as "superhero" then I will say the original Buffy the Vampire Slayer film.
otherwise it's a close run between Supergirl, Batman Forever, Batman & Robin, Ultraviolet, Daredevil and Jumper.

I liked jumper wish they would have made more

RoboCop(2014) maybe thats because its a very bad reboot of the best action movie ever.

The latest Fantastic Four movie. It was kinda good in the beginning but not being loyal to the source kinda killed it in the end. Catwoman had the same lackluster feel.

Oh man, there's been so many garbage ones. Catwoman, Elektra, Jonah Hex, RIPD. The old Cap movie from the nineties is a real howler.

That's tough. It's a 3 way tie

Elektra
Fantastic 4 (2015)
Catwoman

THANK YOU!  People always get mad when I say MoS is Snyder's best work (still only a 6/10 for me).  I hated 300, Watchmen, and Suckerpunch.

You know, after reading some comment here, I suddenly feel the need to watch Batman and Robin.

As for me I haven't watched a lot of superhero movies, but I'd go with Green Lantern 2011 and Iron Man 2 (wasn't a terrible movie but such a let down after the first one).