When a family of bees found a shelter in your house, many time is at the edge of the roof- the soffit
For a while, the bees might be unnoticed, but eventually the house residents will notice that bees have a nest in the house
The problem with this is that sometimes, bees feel that people are too close and they sting. If a bee stings, the bee dies. The rest of the bees will smell the fermomons release and other bees will " attack" the person by stinging into nearby location to protect the hive. So the home owner might end up with many bee stings. If he is allergic, is a big deal. Sometime, neighbors might get stung or children, or pets.
The longer the bee hive is in the soffit, the more likely is that they will find a way to get access to the roof, inside the walls or inside the house. Also the more likely is that they will build honeycomb and start to have larvae for the future generation of bees
When a bee keeper comes to remove the bees, first he needs to determine if honey combs are in. If they are, the combs and the honey needs to be removed. Even if bees will be relocated, if the honey comb remains,, new bees will be attracted to the smell and will come. Also if new larve are left in, due to lack of care they will die and cause infestation of worms into the roof