Why are some cells not fit and others are?
Discussion
they are different because they do different things. in each cell, some things if they are let in will cause the cell to malfunction, so it has protective structures that prevent this. it's not unlike the openings of a building, and the various shapes and sizes and ways that they are opened and what they let in and out.
In this case the cells don't have a choice but to let it in.
doesn't mean the owner of the cells has given permission. that makes it a tresspass and a break and enter.
if I smash a window to get into my own house that's not a break and enter, that's me damaging my own property, which i am free to do.