From Muppet Wiki

Lorne Michaels (b. November 17, 1944) has been the executive producer of Saturday Night Live off and on since the first season premiered in 1975. He has also been a writer on the show. When launching the series, Michaels was responsible for the involvement of Jim Henson, and The Land of Gorch segments from that first season.

Jim Henson spoke well of Lorne Michaels, as noted in this excerpt from an interview by Judy Harris:

I'd be really interested to see what Lorne said, because I really respect Lorne. We talked a number of months before the show ever went on the air. He described the show and I really loved it. I saw what he was going for and I really liked it and wanted to be a part of it...

In a 1999 interview on CNN, Michaels discussed the process of adding the Muppets to the show:

I had enormous respect for Jim, and it was fine for me wherever he was going to head, you know, because it would at least be interesting... We certainly didn't get Kermit. I would have much preferred Kermit and the sort of more joyous characters. But there were some really funny characters in it, and it had a real freshness to it.