Ever have one of those days...
Things are going great, then some random thing derails you with such force that you are tempted to take your ball and go home (or throw it over the fence so no one else can play). David Miller was racing toward the finish in the Giro de Italia when his chain broke. His reaction is sudden, kind of funny, and one of those childish moments most of us wish we could get away with once in a while.
I remember a similar instance from a Seattle to Portland ride a couple years ago. A couple was on the side of the road, and the woman was clearly having a bad day. She threw her bike to the ground and was shouting her frustration to her husband/boyfriend for TALKING HER INTO THIS STUPID RIDE. It was going to be a tough road for both of them.
I can only hope that after throwing her bike, stomping around and generally throwing a tantrum, that her frustration dissipated. Hopefully the guy took her venting for what it was, and that they could both move on, together.