I've won races because I got lucky and had 2 laps of nothing but turbos and mines, and I've lost races where I've picked up nothing but bombs, mines and shields when middle to rear of the pack
it just goes with the game. There's a set probability of each weapon, so I just accept that "**** happens" and move on

my favourite thing about backquakes is when fate has smiled, so you have a shield ready. you can get through the quake with minimum impact and gain some serious ground on the leader.
I've had a couple of really close finishes thanks to people backquaking near the end of the last lap, then catching them as they turn back around