The close-to-home example that came to my mind while reading this is GPU programming, where the percentage multiplies. Maybe there are other similar examples where a large sounding percent needs an exponent and shrinks?
With CUDA you try to keep all threads doing the same thing. Sometimes that’s very difficult, but if each thread does the same thing 98% of the time, is that enough? Well since there are warps of 32 connected threads, you might expect the probability that any thread in the warp diverges to be .98^32, or 50% of the time spent with one thread in the diverged code. 50% still doesn’t sound that bad unless threads diverge at different times, and then 50% warp divergence might mean a 16x slowdown overall. 98% isn’t enough in this case.