It's some sort of conspiracy that's related to your fit issues. I think what has been happening all these years is that your IEM's are being diverted on route and adjusted so that they won't fit and then sent on their way to you.
I am not entirely sure who it is that is doing this or what their motives might be, it may just be the mischevious IEM imps at play. Or the government. Or aliens.
On a slightly more serious note, both Phil and myself are somewhat mystified as to why my particular set of ears seem to pose so much of a problem. I know I've said it before in these forums but it bears repeating, Phils patience and courtesy in dealing with my situation is really appreciated.
If any potential new comers to cosmic ears do have any questions don't be afraid to shoot them an email.