I'd guess that the most common cause is the previously-mentioned "money shift", i.e. overrevving (revving above redline) when downshifting. The other causes you mention are also possible, although not necessarily due to the reasons you give (i.e. oil starvation, but not necessarily during track events - any failure to monitor oil levels over time; overheating, but not necessarily due to improper coolant maintenance - continuing to drive when a cooling system hose fails is probably the most common cause of overheating).I'm only guessing but I would say the #1 cause of NSX engine failure is engine modification, including addition of superchargers and turbochargers, especially if tuning is not not done well. I would guess that number 2 would be oil starvation, during track events. Number 3 would be overheating due to improper coolant maintenance. Not to say any one of those issues caused the damage shown in the OP.