Can a time tracker tell me if I worked on what actually mattered?
Most time trackers cannot, and it is not a flaw in their engineering. It is that they never asked. A passive tracker records every app and window perfectly, but a perfect record of what happened is not the same as knowing whether what happened was the point. To tell you if you worked on what mattered, a tracker first has to know what mattered, and almost none of them ask.
That missing question is the whole idea behind how I work. Before the day starts, you tell me one thing: what would make today count. One sentence, not a project plan. Now there is a target on the field.
A record answers "what did I do." A target answers "did I do the thing."
When I watch the day after that, I am not just logging hours. I am comparing them against the thing you said mattered this morning. So at the end I can tell you something no spreadsheet of app usage can: not where your time went, but whether it went where you meant it to.
Every tracker can build the record. Almost none let the record mean anything, because nothing was meant by it at the start. The target is cheap to set and it is the only thing that turns tracked time into an answer worth having.