"[The recruiters] don't know how to evaluate talent," former Perry High School head coach Preston Jones, wearer of a killer 'stache, told TMZ Sports this week.

"They don't know what's good and they look at all these things about height and speed. They don't look at winners and they don't look at all these things that [Purdy] is."

Before last season's unexpected turn of events (Trey Lance and Jimmy Garoppolo going down), Purdy was just a 3-star prospect in the 2018 recruiting class  ... and outside of Iowa State, he didn't get much attention at all.

Brock chose ISU ... and went off for the Cyclones during his four seasons, throwing for 12,170 passing yards and 81 passing touchdowns. he also ran for a bunch of yards and TDs ... and he broke 32 school records!

Stud ... maybe even a first-round pick with those gaudy numbers, right?

Not so fast. Purdy wasn't taken in the 1st, 2nd, or 3rd rounds ... no, he was the last pick -- selection 262 -- in the 7th and final round of the 2022 Draft ... colloquially known as "Mr. Irrelevant."

He's not so irrelevant anymore ... and Jones thinks a lot of coaches are likely kicking themselves for overlooking Brock.

"There's a lot of guys that missed on him and they're gonna regret this one day," Coach Jones said. "I like to laugh at those guys now."

At the end of the day, Jones is ecstatic it's all worked out for his former QB -- who he calls the greatest offensive player he's ever coached -- believing everything turned out the way it was supposed to.

"It was destiny, it was so cool that it worked that way and it's also kinda been his life's story. Coming out of high school, not getting recruited ... so it was kinda perfect," Jones said.

"It's a great chapter in his book that's not done yet."

And, with a win over Patrick Mahomes and the Chiefs, Brock's story may actually end up being a book ... and a movie.