There are mistakes and there are acts of characters which are very odd given their personal creed.
Why couldn't Harry Potter see thestrals right in the first year? It's kind of hard to avoid seeing someone die when they literally jump in front of you catching the killing blast.
Why Voldemort unceremoniously killed a pureblood James but was willing to spare muggle-born Lily? It doesn't make much sense.
@TheIncredibleHulka But why did he oblige? And why did he tolerate that his servant cared so much about a muggle-born? It must have been a red flag for him. I'd expect Snape to drop dead the moment he dared to present such request.
@CrazyMusicLover Voldemort was lenient towards Snape;if he weren't he would have caught him spying for Dumbledore. He even told Snape that he tried sparing Lily, which means he was open enough with Snape to discuss this. This could arguably atmost be a character flaw, but not a factual one like the one with the thestrals.
@TheIncredibleHulka No, it's definitely not a mistake. It's just interesting fact that makes me wonder if it was intentional or just, as you say, a flaw. Like maybe he was oblivious to him more than to others because he saw himself in him a little bit - being half-blood, hating his own Muggle father.
