Seth Godin brings our attention to the Weber-Fechner law:

The more stimulus you’re getting (light, sound, pressure, delight, sadness) the less easily you can notice a small change. That seems obvious, but it’s worth saying.

If you’re entering a market filled with loudness, it’s harder to be noticed, even if the incremental benefit you offer seems large to you. If you’re trying to delight existing customers, the more delighted they already are, the more new delight you need to offer to turn heads.

This brings to mind the Blue Ocean Strategy.