I found that companies send verification emails immediately, as soon as I enter my
email address.

With previous disposible email services, I had to interrupt what I was doing, go to the services’ website, create a new address, then go back to finish up my original registration. It was clumsy for me.

With Yopmail, I can just enter any yopmail address during the registration process without having to create it at yopmail in advance.

A drawback might be that anybody could guess your yopmail address and steal your registration information. But I open the yopmail message immediately and delete it. No worry.