Super Annoying Tropes

I just wanna rant ngl.

LOVE TRIANGLES ARE ONE OF THE WORST TROPES EVER. I typically avoid stories that have 2 mls on the cover/mentioned in the summary, if you enjoy the trope, good for you. BUT I utterly despise when an annoying 2nd ML spawns. LIKE BRO YOU ARENT IN THE COVER, YOU ARENT EVEN MENTIONED IN THE SUMMARY, AND YOU WEREN'T EVEN MENTIONED IN THE STORY UNTIL YOU PHYSICALLY APPEARED IN THE STORY. GET OUTTTTTT, AND PLUS ITS WORSE IF THEY'RE CONSTANTLY CLINGING ONTO THE MC. If I order a sandwich and you sneak a lime in there, we're fighting (weird analogy ik, I can't come up with anything logical rn). Those fuckass 2nd mls can burn in a ditch for all I care (doesn't apply if they aren't shitty like the ML, but in most cases they are even shittier).
Lately there's been a pattern of evil 2nd mls with glasses like what. Every time I read a story and a semi buff, attractive character with glasses pops up, I CAN TELL YOU'RE GONNA BE ANNOYING then I drop it cause ik the author's gonna let them get away with some crazy bs. Certain characters got that evil aura so yk u gotta drop it, then leave and come back a few weeks later, then BOOM they did some weird shit to the main couple. Happened to me over 10x, my instincts be saving me from reading crappy stories
Why do authors like doing this.