From the very beginning of CBS’s “Big Brother” Season 20, Tyler Crispen dominated the game. A 23-year-old lifeguard from South Carolina, Tyler was a skilled physical player who won competitions. He was well liked. He had the ability to make people feel like he was on their side, despite the fact that “Big Brother” is all about calculating the right time to stab someone in the back, as contestants live together in a house and vote one another out week by week.

But on Wednesday night’s finale, Tyler fell just short of victory — as part of the final two, he lost to Kaycee Clark, the 30-year-old football player from Arizona who walked away with the $500,000 grand prize.

So, how did this summer’s best player manage to tank his own game?

Viewers debated this as #BB20 trended worldwide on Twitter for hours after the finale. But one major reason became clear: Although Tyler was savvy inside the house as he built trust and relationships with his fellow contestants, he seriously miscalculated the best way to navigate their exits once he voted them out.

Technically, the “jury” (the nine former houseguests who vote on the winner) are supposed to keep an open mind about the final two. As “Big Brother” fans know, it doesn’t always work out that way.

“Who has a bad taste in their mouth because of Tyler when they walked in the jury house?” former contestant Will Kirby asked the jury, during a sit-down in the finale.

Scottie Salton (who was evicted, battled his way back into a house, and then promptly evicted again) instantly raised his hand. Sam Bledsoe, who always seemed clueless about the dynamics of the game, hesitated and then raised her hand as well. Brett Robinson, who was in Tyler’s alliance and blindsided when Tyler helped orchestrate his eviction, unsurprisingly agreed.

Yet in the end, Brett still voted for Tyler as the winner. Scottie and Sam did not. They voted for Kaycee, and tipped the scales to her 5-4 victory. Bayleigh Dayton, Faysal Shafaat and Angie “Rockstar” Lantry also voted for Kaycee, though that wasn’t shocking — they were never on Tyler’s side. Scottie and Sam, however, floated between alliances, and Tyler could have just as easily had their votes.

Unfortunately, Tyler made a couple critical errors. He was close with Sam the whole game, bonding with her the first week when she was miserable and lonely. He repeatedly told her to trust him, and she made it clear she would blindly follow him anywhere. Of course, as the numbers dwindled, Tyler was eventually forced to evict her.

Sam insisted she wasn’t offended, but when she got to the jury house, she was shocked to learn that her loyalty was misguided. He was in a six-person alliance that didn’t include her. She and Tyler also had a “final two” deal; only he had similar deals with three other players.

“I felt very secure in that Tyler was going to follow through with our promise,” Sam said sadly. “I trusted Tyler throughout this entire game, and I don’t think I’ll ever fully trust him again.”

During the finale, Tyler continued to dig a deeper hole. In his appeal to jury voters, he revealed that he befriended Sam because she was a “wild card” he could use to shield him from enemies in the house. He also implied he used Sam for a special power she won early in the game, which could help save someone from eviction.

In a post-finale interview, Sam reportedly said she voted for Kaycee for personal reasons and wanted to give her the money based on what she learned about her backstory. Still, Tyler’s speech — which was supposed to impress everyone by explaining his strategic game moves — could not have thrilled her.

Scottie, meanwhile, also thought he and Tyler were pals — until Tyler won Head of Household late in the game and put him up for eviction. When Scottie was eliminated, Tyler decided to gloat in his goodbye video message.

“Scottie, man, I know we joke around a lot about not really knowing what’s going on. But the truth is, I’ve kind of known about what’s going on a lot of the time. I knew you were going to go home this week,” Tyler told him.

That wasn’t a great move, as Scottie was clearly stung by this betrayal.  As Scottie cast his vote for Kaycee in the closing moments in the finale, he simply said, “It’s all about loyalty and respect for me.”

That’s the trick with “Big Brother” — if you’re a player who makes big moves, you have to convince the same people you ruthlessly evicted to give you a half-million dollars. And Tyler just couldn’t pull off that crucial balance.

Luckily, Tyler still won $50,000 as runner-up, and was voted “America’s Favorite Houseguest” by viewers for another $25,000. But after an incredibly impressive game over three months, losing that extra $425,000 is truly an unfortunate ending.

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