a question about the 2 doses required

[Anonymous]

I have a question about vaccines in general-- when you need a second dose to be fully protected against getting the illness, are either of the following statements true:
( if they say you are only 65% protected, but after the second you are (almost 100% protected)):

1. In a group of 100 people having had one dose, are 65% of them fully protected and 35% have essentially no protection? But after dose 2 all are fully protected.
OR
2. Are the people with one dose likely to get a less severe form of the illness, and then after dose 2 essentially not get the disease?

I have tried to write this in a way that makes sense. Thanks!
(Please answer if you actually know, not just have a theory.)

[Anonymous]

Thank you very much for that answer.