Due to the number of variables involved I don't think there can be an exact answer to that.
I have loaded some 44 magnum cases about 10 times and have had 1 cracked neck.
I wasn't keeping track of times fired in those days.
I have never had a cracked neck in 44 special.
Some special cases may have been fired more than 10 times.
Some of the variables on the manufacturing side would be:
The exact alloy composition, how thick is the brass, how many times was it drawn
and annealed, and how carefully was it made.
Some variables you can contribute to:
The pressure of the loads fired, how much sizing is done, how much is the
mouth belled, and do you anneal?
Each time you fire and resize a case it gets a little harder.
Annealing the mouth softens it back up so it won't crack and is able to grip the bullet.
(Most do not anneal revolver cartridges)
Good condition 38 special brass should last practically forever using normal loads and gentle reloading practice.
That's what I find in the 44 special.
Given the price and availability of 38 special brass, if you do get a cracked case just scrap it out.
Here is a nice little introduction to handloading that was a free insert in Handloader magazine.
LOTS of cool pictures.
It's too big to post here directly.
https://uniquetek.com/store/696296/uploaded/Ammo_Reloading_Guide.pdf
If you get a security alert from your browser ignore it.
Their server's certificate has expired.
Worked fine here.