The finals are as difficult as they look.

Finalists have no idea what they're walking into. Viacom Media Networks

In his interview with TV Guide, Murray said producers put a lot of effort into "constantly" changing the show to "keep it interesting" for cast members.

"We don't want [contestants] coming into a season thinking they know how to play the game," Murray said. "We've got to find some ways [to make them go], 'Oh, it's not working the same way as before. I need to rethink my strategy.' We need to keep them on their toes."

According to Us Weekly, cast members typically spend about six to eight weeks on location before making it the finals.

Throughout that time, they are never given any idea of what that last challenge will look like. Not knowing what they're preparing for is what makes the finals as difficult as they appear to be on TV.

As series veteran Derrick Kosinski told Us Weekly, "You know it's going to be long and grueling, but you don't know what it's going to be and you have minutes to try and figure it out."

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