Yes it does flow both ways. Occasionally a Protestant conversion story is posted here and they tend to be vehemently anti-Catholic in tone. I attribute that to their losing the belief in the Real Presence.
Another common reason Catholics leave the church is the divorce/re-marriage issue. The Catholic position on this is very clear. Protestant Churches don’t seem to have a problem with this. That should cause you some concern that the clear message of the gospel is being compromised in order to attract new members.
Then the Catholics have their own set of problems with the SCORES of petted pedophile priests, caught in an unnatural celibate situation, caught in the sin of pedophilia (a rampant problem over the years), ruining scores of young lives as well as their own, and yet the Catholic hierarchy covered up for these pampered elite little boys for decades. That is hypocrisy - and hypocrisy is present in ANY organization where the ambitions of man take control, be it catholic or protestant.
The priesthood of the believer is scriptural and something to stand upon.
Or, it could be that people have heard the calling of the Holy Spirit. Most of the former Catholics I know, it has nothing at all to do with divorce and a great deal to do with doctrine. The point is, of course people convert to Catholicism and of course Catholics leave the church for other churches. Which one is right depends on your theology, and is not an argument that is going to be resolved on a political bulletin board.