In the film 'Sliding Doors', the protagonist Gwyneth Paltrow lives out a parallel life from two scenarios - one where she catches her train, and one where she misses it. So it turns out, the reality where she catches it offers a much happier life than the one where she misses it.
Harry Kane's sliding doors moment may very well have come and gone last summer - when he failed to seize on a chance to join Manchester City. Then in the prime of his life after captaining England to the Euros final, his stock couldn't be higher, with City then willing to pay £120million for his signature.