Why does updating Assigned To and Status not require an explicit Save?

Why does updating Assigned To and Status not require an explicit Save?

Setting the Assigned To or Status fields results in an immediate update to the ticket but changing other fields requires clicking the Save button to update the ticket.

Why the difference?  I find this confusing as there is no indication that changing these fields results in an immediate update to the ticket.

If you have Zoho set up to notify agents when a ticket is assigned, you may make a mistake or change your mind when setting the Assigned To field but the ticket update and notification are immediate.  Same goes for Status if you have any workflows, supervise or SLA triggers based on the Status field.

Also, if you have a workflow to update another field based on an Assigned To or Status change, it initially appears to not work because the immediate updates to these fields do not refresh the display.  You don't see that the workflow has updated the other field unless you refresh the browser or click the Save button.