When selecting reference for the creation of Fillets and Rounds, you have many choices. Most users simply select the required edges. But a better option is sometimes to select the face which results in the automatic selection of the adjacent edges.
In the following example, a solid cube is created and the top four edges are selected for rounds (image below).
Additionally, if a feature (such as a CUT) is made and reordered before the Fillet feature, only part of the intended edge is used for the round, as 5th edge is now created.
Reorder the Cut above the Fillet feature (image below) and the entire edge is not selected as it is now divided by the Cut feature .
The ideal situation is to select the Face (image below) which automatically selects the four adjacent edges.
If the same Cut is made and reordered before the Fillet, the additional edge will still be selected to update the Fillet feature (image below).