What’s luck got to do with it?

And following on from that, why is it that as someone once said to me “you have to make your own luck” when so-called ‘bad luck’ makes itself thanks to sod’s law?! – which by a stroke of irony even has it’s own mathematical representation these days as ((U+C+I) x (10-S))/20 x A x 1/(1-sin(F/10)).