In the OP, I was just asking about when watching a show. The additional question came to me later but I didn’t think it worthy of starting its own thread.
Oops. I missed that you were the OP. I think a short period of buffering when you select what you want to watch is normal. Buffering that interrupts the show means the connection isn’t streaming fast enough to stay ahead of the program though.
“In an evening…”
Another vote for none, or close enough to none that I voted none anyway. Gigabyte plan from Comcast and the TV is near the router (TV is actually connected via ethernet but also has a Fire Stick on wifi).
Hawaii here. Voted 1-5 but that would be more accurate for a two week period and closer to once or twice. Might be a popular show or bad weather or technical problems with the provider. Most connections to Hawaii (Oahu) are satellite or ocean cable. I’m surprised the signal is so robust actually.
Most days it is zero. If I encounter buffering, it’s usually because something is amiss and I need to restart either the router or the eero or the TV itself. And we don’t have especially good wi-fi (not bad, either, just “regular”) through u-verse.
I said zero, but Youtube occasionally buffers. It’s rare with everything else (Netflix, Hulu, AppleTV, Prime, Disney+).
Looks like the unlikely choice is the most popular.
I am surprised at the results but it seems that the culprit might be YoutubeTV. Now that I think about it, I don’t really have buffering with the other providers.
Then almost never.
I have YouTubeTV and don’t have that issue. 
I’ve no idea how often any of my streaming video content buffers; it’s not often enough to really notice. Streaming audio, OTOH…