1. Raven : They didn't need to. He came around in an era full of main event caliber talents. I'm sure 'wellness' and attitude played a part as well. He's known to be a fairly squeaky wheel. He's a smart man though
2. Chavo Guerrero : Why would they? He's not a draw. Even if it were an homage run after Eddie, Rey was way more over and better in-ring.
3. Ken Shamrock: I remember reading about this. I don't remember exactly why though. Again, it could be the same reason as Raven: he came around in an era where there were multiple headlining faces of the company already. He also had a bit of an ego from what I understand and came off as unpredictable at times, threatening to shoot on boys in the locker room and such.
4. Dan Severn: Wasn't really over or main event caliber.
5. Taz : Too small and not that great of a wrestler. Sure, he can through suplexes, but there's not much psychology to Taz
6. Steve Blackman: Why would they? He lacked charisma, wasn't a great wrestler, and they had a stable of headliners.
7. Doink the Clown : because he was an evil clown, then a regular clown.
8. Owen Hart: Austin may be a key component in Owen hitting the glass ceiling but who knows? maybe Vince didn't see anything in Owen.
9. Bam Bam Bigelow: I like Bam Bam. I like his look and his in-ring style, but by no means was he a main event competitor. He wasn't a talker and his in-ring work was best left as a flashy spectacle.
10. John Morrison : Steroids and he probably wasn't ready. He also got a lot of backstage heat because of Melina.
11. Dean Malenko: Zero charisma, on the mic or in the ring. I think Malenko was a better technician than Benoit personally, but he was way too stoic and lacked the intensity that got Chris over.
12. Sabu : He's hot garbage.
13. Shelton Benjamin : They tried pushing Shelton. Shelton just doesn't cut it as a main eventer. Great worker. No charisma.
14. Savio Vega: BECAUSE HE'S SAVIO VEGA!
15. Ron Simmons: I think Ron would've been bigger with Nation of Domination as leader if The Rock hadn't shown up to outshine him. Plain and simple, Ron became the Arn Anderson of the Nation of Domination when The Rock showed up. Ron could wrestle, Ron could talk, and Ron could intimidate, but he didn't connect with the crowd like The Rock