We chose these because they cost less to buy in bulk than others I saw. We handed them out at a Trunk-or-Treat so can't say if a percent didn't glow - but all the ones I saw activated did. I don't know how long they all stayed glowing, but the one I used glowed brightly for 5 hours, and still had a faint glow after another 5. One comment, for what it's worth: some of the sticks are clear - they do glow when activated, but younger kids were pretty suspicious and wanted a 2nd one or to trade the clear for a better color.