I didn't use to track my work and I noticed that at yearly review time it's been pretty difficult to remind what I actually did for last year. I'd go through merged PRs in the main projects, but it's only a tip of the iceberg.
Some time ago we moved daily standup to Slack, and since then I have a pretty good history of what I did each day. I created a wiki page where every 1-3 months I try to summarize all the stuff I did in the quarter (code shipped, dashboards created, docs written & non code work done, like helping X ship Y -- with screenshots, links etc.) and then it gives me a bit of confidence boost during the perf review time.
The only time when tracking work has been really useful was when the Icelandic banks went bust during the crash of 2008. Having a log of work-done helped a little in trying to get paid after my client went down. But, in other cases, I’ve found that the result of the work is the log of work done.