I have been there for 10 months. I will work my notice period. I have had some discussions about not fitting in with the team etc but I haven't implied that I might leave. I've had a week off and decided that life is too short to work in a job that fills me with dread so I've decided to quit.
Is it poor form to quit after only 10 months? Is it poor form if the first time your manager hears about your resignation it's because you gave them a letter of notice? Will people (current employer and future ones) think badly of me?
I've worked so hard for them. I've received great feedback. I just don't like it any more.
YABU - staying a bit longer before handing in notice is the right thing to do
YANBU - quit, life is too short and it isn't unreasonable to quit even if employment has been short