On Chernarus, decals are primarily used to make specific areas (such as concrete surfaces and roads) look more damaged / abandoned. We cant simply add local damage to the concrete / roads texture itself as it would look too repetitive in the end. And so these decals are a great way to add a local damage exactly where we want.
While decal textures were trying really hard to show that there are holes in the road, they ultimately failed alone because they were missing visual depth in-game. Luckily, this was changed with the recent implementation of parallax mapping for decals. And since we have got new textures for roads for quite some time, we have also decided to re-do textures for all road damage decals so the visuals of decals match together with the new road textures (visual inconsistency between old decals and new roads is one of the reasons we decided to postpone the release of new road textures, originally planned for update 0.62). Here are some examples of how medium and small-sized decals look after these changes
These changes (along with the new road textures that you can also notice on pictures) will be available with the update 0.63.