Originally Posted by Duragrouch

Please know, I'm not basing that statement on IGHs in my experience, I haven't used one since early teens. It's based solely on a LBS that seems to be an expert on IGHs, people ship them from around the country to get serviced there. The particular owner/mechanic has been thanked on Sheldon Brown for providing valuable info on a number of subjects. Their web page on IGHs says need annual lube if ridden in rain like our local city all winter. They could be wrong, or just trying to drum up business. I just know that they know more than me. Qualifier: I don't think this applies to the Rohloff or any other IGH with good seals and oil bath lube on everything, both sealed from water well, and consumer-easy to drain and refill.

Scroll down for info on this page from that shop:
https://www.rideyourbike.com/internalgears.shtml