I love this piece by Jonas Downey where he writes for Signal V. Noise:
Somewhere along the line I realized and accepted the truth: nobody really owns anything in a product made by a team.
Whatever ownership you have over an individual contribution is immediately forfeited the moment you commit the code. At that moment, the work becomes part of the ever-evolving organism that comprises a software system.
Each piece of work is a mere pebble tossed into a flowing river. Maybe your pebble will become bedrock—sticking around for a long time and altering the water’s trajectory. Or, maybe it’ll quickly dissolve into dust when new pebbles come along and crash into it. Both of those outcomes are completely natural and worthy of celebration.
When you work in a big company you have to get used to this feeling of your work being obliterated and replaced by something better than what you built before. And being okay with that is a staple of seniority and experience.