Hey Villains you have an opportunity to attack why wait?

LOL Maybe they don't want to attack while the hero is talking cos they don't want to be called sneaky. ;)

I think, when these heroes transform, they are engulf in a magical sort-of-thingie which the villains cannot penetrate. Or probably they enter another dimension when they transform and the villains cannot follow them there.

It must be a manners things, but yeah, I've noticed it too. I remember in one Sailor Moon episode, the villain watched Sailor Moon transform to learn her secret identity but was later killed in the same episode. There is another thing I know happens in Dragon Ball Z, but no sure where else, is when the heroes wait for the already powerful villain they are fighting to transform into a more powerful form.

Haha...that's so true. I also notice that the villains tend to monologue and go on and on about their evilness or their intentions and such. Happens a lot in the shounen series. Sometimes, I just want them to get on with the fight and be done with it. The whole transforming and monologuing is cool the first few times but it gets really old fast. But then again we wouldn't have much of a series if the hero is defeated right off like that.

I now other anime that have that strange factor too, its Digimon Adventure. When the digidestenied Digimons digivolving it take about 1 minute but the enemy can wait for them to digivolve. Then i thinks there is a possibility that the digivolving sequence just can be seen by us the anime watcher only and in the worlf of the anime maybe they digivolve instantly. But that didn't make sense after they release the movie our war game. In the movie Diaboromon attacking the Digimons when they undergoing digivolve and the digimons easily beaten like that. So it mean the digivolving realy takes time and everyone can see the transform sequence including the enemies. That really become strange indeed, at how the enemies would want to wait them to transform before attacking. ^_^