From the perspective of the writer (though not all writers are this rude)

I have at times felt just like this though I've never actually voiced my irritation quite so much. Interruptions have lost me ideas, which I've struggled to get back. They've also cost me time and a little bit of my sanity as frustration takes over.

For all you writers out there, I hope you will actually accept the knock on the door when you fall over with a thump or there would be no more writing. For all those non-writers, watch your step a little. Writers tend to get a shock when woken from fantasy land to face reality. They don't like it.