If there was only one source doing all the ratings, then it would be more of an apples-to-apples comparison.
But, as we know, there are multiple sites each doing their own evaluations and issuing their own ratings. ESPN, Rivals, Scout, 247.
So, we get into these endless discussions/arguments. is a 3* from ESPN the same as a 3* from Rivals?
Are the numeric ratings comparable? If a player is a .8547 from 247, how does that compare to a player with an .8600 from a different service?
I look at all of it like the old sticker they used to put on pinball machines: "for amusement value only."
In the end, coaches will recruit players they like. I have yet to hear of a coach who said "I was going to sign Player X, because I really liked him, but when he got a 2* rating from Rivals, I decided I couldn't give him a scholarship."