I normally finish every episode watch but there were a couple exceptions because I wasn't up them at that time so I finished watching the episode at another time.

I may have done this and never finished them as well, I just can’t remember those times.

I stopped watching OUAT in episode 2 because I wasn’t interested but I returned like a year later and was hooked on it all the way through season 3. Coincidentally, I also stopped watching OUATIW on episode 2 (Alice and Will bored me in the beginning tbh and there weren’t enough Red Queen scenes to balance it out), but about a week later I read a spoiler I liked so I went back to it and fell in love with the show. XD

Yes happened to me with OUAT, SPN, Atypical and My Mad Fat Diary.

I started the first episode of OUAT and My Mad Fat Diary and got bored halfway.
I watched 9 seasons of SPN and half of season 10 and I got bored in the middle of an episode and I decided to quit watching from that day.
And idk why I didn’t continue Atypical lol

I'm pretty good about sticking it out. But sometimes I'm checking out a new show and the pilot is just more than I can take.

I usually finish episodes, but I have definitely done this. The Wire springs to mind for me. So boring.

I can think the Pilot of Outlander. I don't remember if i've done it again. Probably not. I don't like not completing the episode.

Just did this with that show Schitt's Creek. Got halfway through episode 3 and realized it's just not for me and not worth my time.

Many times