A lot, probably most, of my hours on steam are from before they tracked it. I had 3,000 hours in CS:S and it shows 0 because I stopped playing long ago. Steams been around for a long time, much longer than its ability to track games, so I imagine there’s a lot of people with “unplayed” games that they’ve played, plus people like you that don’t show their hours for whatever reason.
A lot, probably most, of my hours on steam are from before they tracked it. I had 3,000 hours in CS:S and it shows 0 because I stopped playing long ago. Steams been around for a long time, much longer than its ability to track games, so I imagine there’s a lot of people with “unplayed” games that they’ve played, plus people like you that don’t show their hours for whatever reason.