Reading through historical accounts, ball lightning moves in strange ways. One recurring thing is that it will go into a building, then leave it.
For something so rare to end up indoors so many times, it must be attracted to the building. But it's not attracted in such a way that it wants to stay.

If a ball were to alter the air around it such that the air repelled it, then it could go through this process:
>ball is outside building
>ball alters all surrounding air to repel it, this would create no net force on the ball except that the building doesn't repel, making it effectively an attractor
>ball is pulled into building
>air inside building becomes highly repulsive to ball
>ball leaves building again

Any other possible explanations for how ball lightning moves according to historical accounts?