I have so many but for GL mine is when the women are just having sex 24/7 and theres no plot. For BL its when the bottoms have boobs, like actually full on breasts *cough*full volume*cough* .
when authors don't know what to do with sex scenes after the couple gets established so they start sum shit with them sex toys. in other words they can't create sexy scenes unless it has that first time interest factor ig reply