Say it is a windy day and you are out on the lake on your jet ski. The wind picks up and it becomes more wavier. You want to try your best to not capsize, or do damage to your ski. You look at the oncoming waves and have to decide how you want to attack them. You could ride parallel with them, you could hit them head on, or you could graze them at an angle. Physics tells you that hitting them head on might be damaging and not the smartest idea. Secondly, riding parallel with them could cause you to capsize, and that would add a lot more physics into the equation. Your best bet is to attack the waves at an angle, maybe 45° unless you feel like getting wet.