Two-time WCW World Heavyweight Champion and former WWE Superstar Lex Luger recently spoke to VOC Nation:

Why Sting belongs in WWE, and why he has always avoided it:
[Sting] felt comfortable in WCW and they always took care of him all those years, so really when WCW and WWE were coexisting he never really felt a compelling reason or time in his career where he thought if he went to WWE that there would be a huge positive move for him. I can't say that I disagree ... [With that said] I don't think anyone could orchestrate the ending part of [Sting's] career better than WWE could. They're just so good at that. Whether it's a Hall of Fame bid or a match with The Undertaker I would LOVE, LOVE LOVE to see that happen personally. I think it would be the cherry on top for his career.

Thoughts on The Undertaker's WrestleMania Streak:
"I was brought in by Matsuda to always be professional, don't ever question finishes. If a guy like Undertaker [wanted to beat me at WrestleMania], I wouldn't have had any problem putting him over, especially at WrestleMania. I understand ... that some guys might be frustrated but I don't understand what they would be frustrated about. It's one match in a career. If you have confidence in yourself, your career, and the big picture as far as where you're going, I don't think it hurts at all to put Undertaker over at WrestleMania."