What is the point in having to fill out 3 applications for a single job once they are interested??

I recently got a job that pays a non-negotiable $20 an hour (requiring a bachelor’s and certifications) and they have had me fill out a full application including my work history, references, and educational background before actually giving me a contract to sign a whole 3 times. This is a well known healthcare organization and I’ve been in correspondence with 3 people already. I just don’t get it. I haven’t even gotten my contract yet or signed myself over to you yet.