Sorting a column three times turns it off

A column header toggled between A→Z and Z→A and nothing else, so once you had sorted by Owner there was no way back to the order the list keeps for itself (newest first, or the sequence the process actually runs in) short of reloading the page. And that order is usually the useful one.

The third press on the same header clears it. The arrow says which of the three it is in, and hovering it says what the next press will do.

It is in the table every list shares, so it is every list in the suite at once, and the related lists inside a record too.