ELi5: During the PS1 era, why were some games so massive in data size compared to other games of similar length?

Question

I was looking at older games that I played as a kid. Lunar 1 had 3 discs compared to Breath of Fire III that had 1. I remember them both being similar pixel art styles and similar lengths. What made Lunar 1 require so much more data than BoF3? Was it the cutscenes? What was the major contributor to high data requirements during the PS1 era?

In: Technology

Answer 1

Most of the time the answer is FMV sequences, and Lunar had plenty of those. Final Fantasy as well.