“If you haven’t been fired, and no one has taken you aside to ask about your performance, then probably you’re meeting expectations.”
Developers who finish their tickets early and beg for more of the same are training their employer to expect it. Whiles spent 20% of his first job learning Haskell, which did nothing for anyone that quarter and made him a better engineer. The company sets the bar. It never tells you when you have already cleared it.