What is SCRUM?

I've spent 15 YEARS in the trenches with SCRUM.
After going through a phase of exuberant optimism (~12 years ago) a protracted disillusionment phase phase followed.

Disillusionment gave way to a phase of bewilderment:

• Does anyone actually know what SCRUM is?
• Is SCRUM really a 'thing'? 
• Is SCRUM just a word?

 Next came a phase in which I was convinced that few, if any people, know what SCRUM is. With out question, it is not even close, folks simply don't know what SCRUM is and therefore it is just a word not a 'thing'.

 I have just now, in a sudden flash of insight, realized the simple truth:

SCRUM is whatever management says it is.

Get used to it.