Lol, I could go on all day about why I don't like Storm...although I'm sure everyone is tired of hearing it by now. But, since you asked, I'll give you a brief explanation
Storm has combos that involve multiple grabs. I dunno about you, but I can't stand having to sit through 4 grabs in a row. For some reason, it seems like when the grabs are a part of the combo counter, it's almost impossible to tech hit out of (anyone else noticed this ??? ). Another reason I don't like her is because her infinite is WAY too easy to pull off. Yet another reason I don't like her, is because on X-Men vs. SF, you can make her fly off of the screen, then float down super slow while you charge your super meter with HP, or do a Typhoon if your opponent tries to get close to you. Most decent Storm users that I've played resort to cheap tactics, and it irritates me, basically.
But, if you like Storm, by all means, vote for her. And the same for everyone else. Vote for who you want.