Because Freiza set the standard for Dragon Ball Z fights. They hype before his appearance was immense. "Stay away from Freiza!" and then when he finally appeared, he delivered. Nameks, Vegeta, Krillin--Freiza made a fucking impact. And when he finally faced Goku, he just kept getting more and more powerful. It was like there was no way Goku was going to win.
What did Cooler do? Show up, beat up Goku for a couple of minutes, and then get his ass kicked.








