If you want to avoid this problem, one should again emphasize with a normal wall paint over the repaired area. This "sealed" the place and also ensures that you do not see the point. In places where you do not worry that you (with clothes), or where it's over no matter touches, you can probably skip this operation.
If the mass once Dried it forms a nice firm surface with the wall is crumbling and not (just like in other cheap pastes the case). For smaller repairs definitely a recommendation.
For those who wonder whether you can order zukitten a dowel hole. Until about 1 cm can you can create it with a good application. In größren holes need I think multiple applications so you have created a background. Shortcut: Yes, a dowel can plug up easily.