But then again, no one really knows Hosmer's ceiling.
"We have no idea what [that ceiling] is," Royals manager Ned Yost said. "He's a guy who can run, can hit for average, can hit for power, does winning things on the basepaths. He's a Gold Glover who is probably the best in the game at that.
"And he hasn't even reached his potential. We saw a lot of it last year, but there's more in there."
Hosmer certainly had a breakthrough season in 2015, smacking 18 homers with a career-high 93 RBIs. He hit .297 with a career-high .822 OPS.
Even Hosmer, 26, thinks he can get better.
"You're always learning in this game," Hosmer said. "You're always striving for new heights."
"I really don't think about that stuff," Hosmer said. "That's not why I got into baseball. I love winning. That's how this team thinks. If the other stuff happens, great. But that's not what it's about."
Still, Hosmer's teammates have seen his game continue to ascend.
"I wish I was that good at his age," said Lorenzo Cain, who at 29 last season had his breakout year. "He can pretty much do it all."
What has scouts and coaches wondering about Hosmer's ceiling is his athletic frame -- Hosmer is 6-foot-4, 225 pounds, with strength everywhere, from his long legs to his upper body.
"I've seen very few guys, especially left-handed guys, who can drive a ball out of the park at Kauffman Stadium to the opposite field," Yost said. "That is just tremendous power. You just don't see that."
Even opposing scouts sometimes seem in awe.
"What I see is someone who keeps getting better and better each year," one rival scout said of Hosmer. "He seems to pick up something new every spring and then you see him take it to the regular season. The sky is the limit with him."