CASA oversee many different operators and if one has no defects on a twenty year old piston twin over a 100 hours, yet the others have ten defects written up it suggests that either they are incredibly lucky, spend a fortune on preventative maintenance or don't write up snags.
Overseas, there was an airline which never had a defect occur on an outbound sector. Anything which went wrong always happened on the leg back to base.
CASA are like the tax office, they see what everybody does and can pick up something out of the ordinary. If you claim for a medical on your tax return and your doctors bill is ten times the average then expect a query.