Age, experience & luck
The services used to reckon there were several high risk points in a pilot's career, as his/her experience increased. They had - and probably still have a system which take a more careful look at pilots as they approached those zones.
I don't recall the hours involved, I think one was around 250-300 hrs then around 1200 or so. There is a third higher hour point I think. The first being a 'know-it-all' point, the second being complacency where we start thinking it's all too easy. A good fright helps - that is where the luck comes in. You have to survive it, or just be a prompt to others.
Still as a famous golfer once said - I think it was Sam Snead after sinking a particularly difficult very long putt - "It's amazing. The more I practice, the luckier I get."
Ask some of our military colleagues. I expect they will know where the high threat intervals are.
I think the Gompertz curve is slightly too simplistic for this purpose. If you plot risk of accident against experience (hours) I suspect there are a series of waves. Logically each wave will show features somewhat like the Gompertz curve, since feedback helps the surviving pilots learn from the mistakes of others, thus reducing fatalities until the lesson gets overridden with time.
Hmm, after 40 + years kicking around in aviation I guess I'm one of the older ones now, though there are some very much older wiser birds on here !