Even the newest watches have 18 hour battery life, so of course one that is almost a decade old would be the same or worse. It's actually amazing that it still lasts a whole day after all this time.

Yes. I use a Series 2 and need to charge it twice a day. :)

Yes. 18 hour battery life has (I think) been the touted range, up until the Ultra came along (excluding low power modes).

Yes, its almost 9 years old

No. It is not normal to charge your device. Unless of course, you intend on using it.