CX-9 2009 Intermittent starting…Any ideas?

[CoopMA]

Advice, ideas on CX-9 2009 with 140,000 miles has intermittent starting problem.
This happens ~1 a week.
Had to turn the key 10 times before the starter engaged. All the dash lights come on when you turn the key but the starter does not engage.
Battery is 14 months old & I thoroughly cleaned & sanded the battery terminals and connections and it still does it.

What to check?
Grounds?
Starter?
Other?

 

[rowlands57]

The ignition switch could be worn out at this point? The lights come on regardless once you reach the run position, it's the start that could be giving you issues. Given that it eventually does start it would seem that all the other components down the line are OK once they get the signal.