Originally Posted by kovidgoyal
Waiting would make it a lot less robust. What if calibre crashes or you decide to quit aborting the jobs or you suffer a power failure. If you are going to send a lot of books I suggest you bulk convert them first, and then send, then there will be only a single metadata.
I was not aware of the trade off. (Power fail is no problem, my APC UPS runs 1+ hr
when only 1 desktop is running)