Firstly, sorry if this is not an appropriate question - but it is one that has bothered me for a long time.
I use LaTeX all the time for writing technical documents and while I often convert to ps, there are also situations where converting to pdf is contextually more useful. Since LaTeX is run as an independent process, it (or a related batch file) will update the pdf file on disk. For common ps readers this causes an automatic refresh. But with Adobe Reader, it locks the file and so even prevents updating the pdf file. I have to close Adobe Reader and then recompile the LaTeX and open the Reader again (yes, I am aware of Sumatra PDF - which only makes the Adobe behaviour stranger).
Over the past quite a few years, I have occasionally gone to the Adobe forums and asked about this feature. I see many other people also asking for auto refresh. And the responses from Adobe are always curt and essentially say that such a behaviour is impossible or prohibitive to implement. To the contrary, my own experience suggests that it should be fairly easy to implement. I have heard several comments like - if the file is a gigabyte it cannot be stored in memory - but, my files are never that large, and if the file was too big to auto refresh one could just say that when it was opened. And so on. The reasons given always seem spurious.
My question is - why is Adobe so persistently resistant to having auto refresh?
To clarify - is there some foundational technical problem that would require a strong rewrite? Or is this something to do with a business model?