Look, I'm not going to claim that when Whiplash debuted in the late 60s, he had a great costume...or even a good one.
Yeah, pretty silly. But Gene Colan made it work. The color scheme proved a good contrast to Iron Man's. And while that normally would be enough flying-everywhere fabric to drive Edna Mode mad, again it makes a nice juxatposition with the sleek but metallic armor.
Later, in the 80s, for reasons, he became Blacklash. Stupid name, but perhaps a better costume:
Again, not the best, but I kind of like how it evokes the Zorro/19th century man of action feeling, a look not inappropriate for a man with a whip.
But then came the 1990s. Oh, 90s, was there nothing you can't ruin?
Yes, someone decided that dressing up Whiplash in full fetish gear was a look that we wanted in our villains.
How bad, terrible, awful was that costume? It was so abominable that when Iron Man 2 came around with a godawful design...
..and the comics felt the need to mimic it...
...they actually looked good compared to the 90s version.
So that's how bad the 90s were--they made crappy things look good by comparison.