Vanilla Skyrim is an especially annoying specimen in this category, because it has this weird "S curve". With low levels most enemies are way stronger than you (ok, that's good, a level 5 player shouldn't be able to defeat city guards, for example), then there is a "growth phase" up to ~level 40-70ish (depending on play style) where the player is on par or better than NPCs, and after that the player's abilities level off and NPCs continue to grow stronger, so a high level player has a hard time again against NPCs of a class that she could previously defeat easily.

Which makes no sense at all.

Luckily for Skyrim the game thrives on mods anyway.