There are lots of ways to find out how good a transfer player is before they arrive on campus. You can look at stats, or portal rankings, or, and maybe most importantly, you can see how the fanbase reacted to the player's previous school. For Missouri fans, losing Marvin Burks was a kick to the gut. He immediately became one of the best safeties in the portal.
Wisconsin had to work hard and probably open up the checkbook to land him, but Burks is a stud, and his play on the field and stats tell even more of the story.