In my OW dives, done here in the Pacific NW, we did nothing but skills the first three dives and a tour for the fourth dive. ...
At the end of the third dive, we were told we were through with the skills (yay!) so our next dive would be just a fun tour with a DM.
Sounds great, but if it is PADI, it is a standards violation.
You are not supposed to do any skills on the first dive, other than what is necessary to get in and out of the water safely. You are supposed to be getting comfortable with diving and the environment. It's a good time for sight seeing.
A number of skills are dive flexible--they can be done on any of dives 2, 3, or 4.
Dive #4 has only a few specific skills associated with it, but they are supposed to be done on that dive, not on one of the previous dives. One of them is the mask removal and replacement.
There are neutral buoyancy and mask skills on each of the last three dives. Some are repetitive, but the idea is that with the experience of each dive, you should be getting better at them and showing improvement.