I also like to leave it until a whole season is out, if not the series. Mostly because of my impatience, like Arianna, and I really just want to get it all at the same time, so I can watch it at my own pace. I only watch the show on a weekly basis if I am really interested in the it, which currently are only Madam Secretary, South Park and NCIS: New Orleans. Then maybe X-Files when it comes out in 2018.
I also absolutely hate cliffhangers, especially end-of-season ones (still have not forgiven Criminal Minds: Suspect Behavior for getting cancelled on a cliffhanger) or arcs that continue through several seasons. Similarly to Sky, if the whole show or season is out, I usually spoil myself on some things, especially if it concerns my favorite characters.
Thank you Dario!