I have an action: Wait for Event: When an item is changed (Output to Variable: related item1 ).
From what I can tell, this event is triggered whenever ANY item in this list is changed. So, all the workflows attached to different items in the list are restarting.
It can also be possible that all items in the list are updated when a single item is modified by the user.
In any case, this is not workable for me to send an email when an item is changed.