I have worked with people who have 8-10 years of experience and are still mid-level in both skill and professionalism, know that they are, and are fine with it. They get their joy from other things in life and are totally fine coming into the office and doing the bare minimum to get by and going years without raises or bonuses because of it. Again, this is a conscious choice these people are making, they're not being taken advantage of or anything.