Yes, this is a very important point about removing the batteries between usage.

I've tried all three steripens, the original, adventurer, and the new Journey.

The original and journey have a major design flaw. If you store them or use them with the prefilter and turn them upside down (wand up), some water seeps into them and short circuits them until they can thoroughly dry, which can take days in a humid environment. Therefore, I just don't use them any more.

As long as I remove the batteries, the adventurer has proven to be reliable.