Tar is a weird and fickle phenomena, at least from my experience.
No rhyme or reason, or consistent cause that I've ever determined.
It just happens sometimes. I recut, puff lighter, and put the cigar in my mouth a bit more to keep lips/tongue off the head as much as possible.....................and then ditch it if it still tasted crappy.
Acrid taste can come from tar, poorly fermented tobacco, RH that's too high, among other things.