An on off switch would have been nice because batteries have shelf lives a lot longer than 2 years. I have lots of other multi-meters and I am retired, so I won’t be using my moshimeter very often. Having to change the batteries every 2 years is wasteful and risks them corroding. I have the same problem with other instruments. I have a sound meter, a micro scale, a micrometer and a clamp ammeter that all are permanently on but I only use them very occasionally. At least with those I can remove the batteries easily to extend their lives otherwise I would be getting through a lot of batteries mainly doing nothing. Two years might seem a long time to a young person but at my age it isn’t long at all. New batteries have a shelf life of about 10 years.
I put the moshimeter into transit mode when I am not using it.