I understand the statement, but everyone just keeps making this type of statement, like it was handed to Moses on Mt. Sinai. You may be right, but I’m not sure it’s been proven.
What is an “intent of resignation”? If I tell my boss that probably around the first of the year I’m going to retire and spend more time with the family, then I agree that is nothing firm that he should rely upon. We will have another conversation, probably late October, to see where I am at with this thought. It is a courtesy that I am extending that I did not have to do.
If I tell him that I am quitting at the end of this month, then that is more definite and more like a resignation and not just an intent to resign. It was still a courtesy to give him notice, but the period of time is much more firm.
To take your position to the extreme example, could I say that I quit, just as soon as I get my stuff out of my desk, but then, three days later, noticing that I had left a dime in the upper right hand drawer, rescind the resignation as the condition precedent had not been satisfied?