Sweet potatoes outside are usually roasted to produce sugar liquid

So my analysis is

In addition to the problems with the sweet potatoes themselves~ (Sweet potatoes can be used to make starch~ they contain sugar. Not low) but the heat is not reached

The roasted sweet potato oozes sugar liquid from somewhere in the skin. The skin is also relatively hard ~ there is a gap between the skin and the flesh of the sweet potato

Like this It proves that the water content of sweet potatoes is also less. The less water content will naturally make them sweeter

That’s why they are not baked well