Staying to long on a project I didn't want in the first place.
I have always been more interested in UI in general, be it web front-end or desktop GUIs. My very first project ended up being DB/back-end(MS Access/SQL Server) on 10 year old tech, ALONE. I did have someone in an advisory position, he was a DBA, but he was always busy on his main project. I did build them a SPA to test the waters in upgrading but it took so long as I didn't have a proper mentor for the web.
2 months in to my next project, having a proper mentor, I could rewritten that SPA in half the time and twice the quality.
Part of my problem was I had issues with questioning authority, but I've realized, as part of a team they sometimes need to be questioned to:
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