That moment when you realized......

[Rostum]

Creating assets is a long, long, long process. Each asset requires a long time to produce;

Just to add to that, making a concept is a long process in itself. It goes through many iterations, quite a lot of quality control and must be checked with creative leads (who are incredibly finicky and rightfully-so). There's also rigging the game model to be ready for animation, which usually requires someone with specialised skills and a long time to produce (I used to work as a character rigger and animator) - needs to conform to internal standards for the animation team.