Stupid question, OSPF.

Hello r/networking.

I have a job interview tomorrow for a very small company who wanted somebody with little to no knowledge on OSPF, he just wanted somebody that understands computers in general. I have been building PCs and gaming for 10 years, so I thought I'd give it a shot since I'm recently out of work.

He wants me to learn as much as I can over night to see how quickly I can pick up on this. So far I've gotten the basics of what it's used for, I understand that SPF is fastest path, similar to a GPS in your car. Area, how all Area have to touch Area0 and go thru a Area Border Router if you want multiple area, LSAs and LSDB. But he wants me to answer 3 key questions, What is OSPF used for? Why/Where would you want to use OSPF? And Why do we used OSPF? I have answers for What/Where. But I can't for the life of me figure out what I want to say for, Why we use OSPF? Any help is greatly appreciated and I'm sorry if I'm breaking any rules in this sub. Just trying to learn/land a gig.