As I understand it and remember it from 5 years ago, it's like this:

1) The horrible level-scaling means if you don't max out your END then eventually you'll struggle to progress due to the mobs' END being increased way more than you unless you do: there are numerous comments on the Wiki and web forums describing the 'leveling problem'.

2) The only way to level END is to take one of three skills, none of which from a 'role playing' or lore PoV a Khajiit is reasonably going to have.

3) At best, a Khajiit gets 4 HP per level with a starting END of 45.

So, unless I turn the difficulty down to EZMODE I see no way a Khajiit is a viable race.

What am I missing?

Increasing endurance early and aggressively is popular among those who get hit. If your Khajiit expects to run around bashing things with a sword and trading blows with foes, it is worth considering.

Perhaps not so for a stealth character however - and it sounds like perhaps you perceive Khajiit as stealthy.

My wood elf is all about not getting hit - a glass cannon as it were. Bow, poison, sneak, illusion, conjuration, loads of detect life and a very cautious/patient playstyle render her very good at it. She started with 30 endurance. 700 hours of play (at normal difficulty) later, her endurance is still 30, she has a tiny red bar and has never been killed. She can take one or two hits, but not much more than that - it is quite a skill to build a character around not getting hit. I find it creates a welcome challenge. Her philosophy is stealth, backed up by 'command, confuse, disappear'. If it works for a little wood elf, I'm sure it would work for a Khajiit.
:foodndrink: