Engine Cut Off Switch (ECOS)....ahhhh yes.

In the Basic Rider Course, we teach the students "Thumb, Key" to shut down the bikes.
This exercises their muscle memory for using the Engine Cut Off Switch and hopefully, if they ever "need" to use it, they can.
In the BRC2 and ARC, we tell the students to ride their own ride, shut down as they see fit.

As TaxFree pointed out, yes, it's an extra step.
The LEAN/6 Sigma part of me wholly concurs.

But then the test pilot in me kicks in.....
- Systems and subsystems must be exercised in all positions to ensure they work and work well
- Working vs. working well: regular exercise to ensure consistent, proper operation and avoid any oxidation build up as previously mentioned.
- The F6B ECOS has three positions, two off and one Run

As a habit, I alternate using the Up & Down positions to turn my bike off.
My thumb likes the pushing to the Up position for emergency training as my hand is already on the throttle and it's one movement to the left to turn off the bike.
That's a muscle memory item I'm only too happy to have.
And, yeah, I don't want to be that guy that has to cycle his pristine thumb switch 50x to get his bike started.
I know mine is working well.

Also, it maybe valid to use the ECOS for fuel injected engines or not (first I've heard of that).....any of our technical types wanna jump on this one?
Cheers,
Steve