Many writers tend to create characters before they even decide on the general take on their story. They take inspiration from their creations and produce a new world on which the rest can be based, while at other times the previous designs are discarded or reinterpreted. The latter case is happened in My Hero Academia with Tenya Iida.
After Kohei Horikoshi had completed Sensei no Bulge on Weekly Shonen Jump and ended with a rejection, he started the foundation of My Hero Academia. The world of heroes with Izuku Midoriya, which we now know by heart, had not yet been created when the mangaka created the character of Tenya Iida. At first, Horikoshi presented him with a completely different look than the current one. He preferred a grown-up character, laughed and had long blond hair. It was only after settling on the school setting that he laid the foundation for the iida we know today, even if, as you can see below, he had a much darker than serious frown.
And still in the picture below, Horikoshi showed that Look first with Tenya Iida's costume. The 1A class head really looks like a villain with a mask that resembles an animal skull. The prototype of the costume was then completely discarded in favor of the current one, which we saw in action several times during the hero missions. These changes still affect the mangaka today, as the draft cover of My Hero Academia 30 shows.
Do you know how much the Deku costume costs?