[quote=@Rilla]
Because you should probably always start off as your primary form, hence primary. Why transform into your primary form?

I've almost  never seen it used well. Kei'taro has one, but it's dependent on it being charged, and only lasts x amount of turns, doesn't heal him, and he can't use most, if not all, of his abilities in it. 
[/quote]

Good ol'hypocrisy.

[quote=@Fallenreaper]
<Snipped quote by Rilla>

Ah... the joys of BSing in Anime. Ironically, Iron has a transformation ability but it's more scene related than actual damage or willing. It had to be during moonlight though in later versions he could learn to it by will, but that didn't auto heal him and he couldn't use his weapons really. Come to think of it, if I ever use it in mid battle, I'll likely nerf it. 
[/quote]

That's a pretty common staple in writing to be honest. Usually you will see a character get the stuffing beat out of them only for them to then catch a second wind "Cause I'm the hero!" even without transforming or whatever. Though I can't really think of an anime where another form healed the character in anyway. In the cause of DBZ at least just going into another form required energy and effort to maintain, hence why they got knocked out of it allot.  

Frieza's 100% form was slowly killing him. People probably overlook the downsides to these power ups all to often. 


[quote=@Rilla]
Then he's not really transforming in battle, which, is more or less the point of a transformation.
[/quote]

What exactly do you mean by transformation then?

I don't see much a problem with it as long as it is properly done.