A lot of junior developers get a lot of satisfaction out of learning lots of new stuff. Their brains are fresh and are a sponge for anything and everything. However, this does fade a bit (but shouldn't go away, a byte for another time) as you get more senior.
However, I believe that as developers progress in their careers, they should also try find satisfaction in teaching. Imparting their knowledge to the next generation. You must remember this pay it forward mentality. You were only able to learn as much as you have because someone taught you - not just in a classroom, but at your desk, in a pull request, in a blog post, a conference or even a colourful instagram account.
I think truly senior developers find that balance between wanting to learn and wanting to teach. Leading others and forging the path.
Heads up: As with any terse bit of advice, there will be exceptions of course, and subtleties and nuance that can't possibly be captured in a Byte of Wisdom. This has been what I've experienced, I'd love to hear yours in the comments too!
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