Starter/batt disconnect switch

[ontherocks83]

So this may be a dumb question but as that my boat is 30 years old I am not familiar with new set ups.

On some newer vessels I have noticed that along with your battery selector switch there is also a starter motor battery disconnect switch. Essentially will either supply power to or completely disconnect your starter from the battery. I'm curious as to the reason for such a switch. Having always had my starter connected to power I can't see the reason for wanting to disconnect it regularly. Like I said may be a dumb question but I am just curious.

Thanks