I don't think I understand why this makes a difference. Wasn't numStatusBars still in scope at the point the later check occurred anyway? 😕

The PrintStatuses method is used as a callback and is called every ~second to print the current status.

The first time it's called, the progress bar and the status bars haven't been initialised, so the code behind if p.progress == nil is executed.

The second, third, ..., nth time it is called, the bars have been initialised, which means if p.progress == nil is false and 🐛 the numStatusBars stays 0 🐛 , which then leads to the "which statusbar do I use to show progress for this new worker?"-check to result in "no statusbar left".

The PrintStatuses method is used as a callback and is called every ~second to print the current status.

Aha! That was the bit of context I'd forgotten. Thanks for that!