#2 To protect AJ Styles from losing to Brock Lesnar again
AJ Styles and Brock Lesnar put on a great match at last year's Survivor Series, where it seemed like at one point, Lesnar would lose to Styles. Lesnar did eventually win, but the respect for Styles among the WWE Universe only rose following that match.
We were set to have Part II of that match at this weekend's Survivor Series, but instead, we'll see Bryan and Lesnar will face off against each other for the first time.
Perhaps WWE changed the match to protect Styles from another defeat and make him look strong, showing the WWE Universe that he is one of the best in the world.
Even the finish to the match against Bryan made Styles look strong as he was defeated only after Bryan hit him with a low blow and not a clean finish. This means that the WWE still consider Styles to be the top dog on SmackDown Live and WWE, and hence it will only be a matter of time before he's back at the top, challenging for the WWE title.