I just realized that only 25% of my characters were really Nerevar reborn. Maybe Azura and the old Emperor are so eager to get rid of Dagoth Ur that they are trying to recruit every likely looking adventurer they can find?

Do others have characters that never completed the Morrowind main quest? Why didn't they fulfill the Nerevarine prophecies?

I just realized that of all the characters i've ever used in morrowind, the only ones that finished the game were dark elves.

Both my Dunmer characters were the Nerevarine too. It seems that the Dark Elves assume that the incarnation of an ancient Dark Elf hero will also be a dark elf. It would be much easier for them to accept a fellow Dunmer in that role.
I've also had Altmer, Bosmer, and Nord Nerevarine characters. Would the xenophobic Dunmer ever accept a Nord as Nerevarine and Hortator? He would have to be a great and good hero.

Would an Orc or beast race character ever make Nerevarine? Would a vampire or werewolf? Not so far in my Morrowind.

actually, i recall once i had a vampire implerial, then he lost his vampirism, then i got bored and became nerevarine. with me, whenever i use a non dumner race, i don't do the main quest. they always turn into redoran masters, or muck farmers.

Yes, it gets boring to complete that long quest over and over again. The quests aren't really exciting and when you have done them twice, you really don't want to do them again.

I also played the alternate way of finishing the main quest. Since this is not the spoiler forum, i won't say too much except that in this alternate way you get wraithguard yourself, instead of just having it given by vivec, after lot's of quests.