The mechanism of adhesion and bonding is simply due to physical contact, the hardness of the surface of the pottery
They are difficult to integrate with the glaze, and this determines the "durability" of the adhesion of the two.
Some surfaces are also very soft.
In order to be able to make the glaze stick better and more durable,
There should be some pottery soil in the glaze composition so that both are suspended in the aqueous material and the dried layer hardens.
If the pottery is very powdery, it is a sign that the soil is pottery
Add more ductile, add a little bentonite or add a stiffener like step.
Add steps to the glaze to make it stick better to the pottery.
If the glaze is dispersed, it probably lacks the necessary slack to deal with
There are small irregularities in the pottery and it holds its place firmly.
Wetting agents are present and can be added to aqueous material to improve adhesion.