I'd hazard a guess that it was loading/fatigue. He flogs his body more than most and it was some pretty tough conditions over there. But as I said, just a guess.
I struggle to digest the fact that kohli has won 7 consecutive tosses at home. I refuse to cry conspiracy but that's some extremely good luck!
As for us, not good enough really but it was tough over there losing all three tosses so always getting the worst of the conditions is never a good start, albeit most will say that's just an excuse - it's also a legitimate factor. Remember SA feared worse than us in their most recent test series in India - which funnily enough kohli also won all three tosses!
I've lost 14 tosses in a row over the course of a season before, this sort of shark can happen. Even 'tails never fails' couldn't help me.
I generally can't decide what to do when I win the toss so I find it easier when they win and they then have to make the play...and then we win anyway haha.