You're faced with a very simple choice with outdoor furniture.
Leave it, and learn to love the silvery grey result.
Or finish it, but then you'll have to sand and scrape it every one to three years and re-finish. You'll have to do this forever, but if you subsequently decide that's too much like hard work then you'll pay a penalty. Because then you'll have a good few years where it goes black and mildew-ey, as microbes feast on the oil in the decaying finish.
So, if it's a truly precious thing that's a joy to behold then sign up for a lifetime of finishing and re-finishing. But for anything less then leave it unfinished.
However the worst outcome is the one most people choose, initial finishing but then lose their enthusiasm in subsequent years and so end up with a mouldy monstrosity.