The loading bar will lie to you about how long it takes. It still gets to 100 if you don’t close the tab.

Estimates are wrong in both directions and a progress indicator is not a promise. What it does tell you, accurately, is that something is happening. The frustration comes from trusting the number rather than the process, and the damage comes from acting on that frustration by quitting.

When something is taking longer than the estimate, separate two questions: is it still moving, and can you afford to wait. If it is moving, a wrong timeline is an annoyance rather than a reason to stop. Check that it is progressing, then leave the tab open and go do something else.