There are many reasons for listing of some token:
- Reputation of a developer team;
- Project success;
- Soft cap/ hard cap was reached or not.
It may depend on the exchange also. I know a good project and it could not access for one exchange for very long.
Since the name token consisted of two characters.
All of the big exchange justify about the project details before the listing progress like as project is legit or not, funding amount, soft cap reach or not. Binance listing is very difficult they arrange vote competition for listing because there are no chances to list random project. Other many good exchange listing first priority is exchange fee than you can get quick service.