Hello!
Peeling can be caused by a number of factors…whether alone, or all-at-once.
* “Chalking” of old paint if not cleaned off WELL.
* Existing paint was letting-go anyway…
* Age of existing paint,
* Moisture problems behind the claps,
* Excess moisture inside house…
* Applied in “too cool” weather…
The list goes on…
If it’s an older home, the possibilities-list can be very long.
So…please provide a “background” of your homes’ paint/siding history…
What exact prep was done (or NOT done!), how big an area involved, and exact brand/types of paint and primer used.
(Some older oil-base paints, that aren’t well-adhered anymore, can literally be pulled off the substrate due to the “pulling” nature of modern Latex paints!)
>>> If the peeled-off paint is a different color on the backside, that means your old paint has just “let go”, and needs to be removed.
Faron