#1 Becky Lynch and Charlotte Flair's title exchange - WWE SmackDown
In terms of WWE stars going off script, there is no bigger example in 2021 than the awkward belt exchange between Becky Lynch and Charlotte Flair. This idea was doomed from the start, with a swap being a lazy way to switch the titles following the WWE Draft.
Anyway, Flair was supposed to hand over her RAW Women's Championship before receiving Lynch's SmackDown belt. The Man was reportedly planned to hold both titles and tease becoming 'Becky Two Belts,' but that did not happen.
As Big Time Becks reached out to grab it, Flair pulled it away and threw it to the mat. Sonya Deville, who was moderating the segment, tried to maintain some control to no avail. Becky Lynch proceeded to throw the SmackDown Women's Championship at Charlotte Flair.
Before the segment could go further off the rails, Sasha Banks came out and targeted The Queen. However, this remains one of the more infamous moments in recent WWE history. The two of them had a heated confrontation at the back afterward.
This formed the basis for the feud between Flair and Lynch heading into Survivor Series, which culminated in a brilliant match. So, rather fortunately, this segment diverting from the script ended up in WWE's favor.