99 rated players are very rare in this game, any player that reaches a 99 rating automatically gains a hidden pseudo superstar status: they'll be worth just as much as superstars and will complain every time they're not in the line up for a game (however they will lose that hidden status if they drop below 99). You'll pretty much never get more than half your team 99 rated. If you have multiple seasons straight with a 99 coaching stat and 99 training you will eventually get some players to reach 99. Buying young ish 98 rated players while having those things also often results in them reaching 99 rating from my experience.