Isn't that where difficulty factors in? If enough people quit mining the difficulty should fall so low that eventually it would become profitable again.
Technology is going to improve also, mining should continue to get faster/cheaper.
No, not really. What I'm saying is that with everything working as it should... difficulty doing it's thing to regulate block discovery times, and the design of DGB being such that the block rewards reduce over time... there comes a time in the not too distant future where block reward drops to less than 1000 (around 5.5 years out) and then at around 10 years out it's approaching 100 DGB/block. Point is... the currency is only useful if it can be used... and it can only be used if there are miners to verify transactions...maintain the blockchain.... therefore without miners... well... you see where I'm going with this.
It's not just a DGB question... any long term coin that has the potential to survive... what happens if nobody bothers to mine anymore?