No, it’s supposed to make an instrument sound more in tune than if you tuned the strings to an equal temperament. There are numerous mathematical explanations for this which, in 50 years of playing have largely passed me by. If you play guitar and have ever noticed that you need to tune the B string slightly flat, you’ll know what I mean.
As far as “wet” tuning is concerned, my observation is that it is often used by beginners, people who’ve never learned to tune properly and it was more popular before the electronic tuner was invented ;) as for me, I’ll worry about it when I’ve exhausted the possibilities of playing in tune.