The number of coins in a project and the rate that they are created is arbitrary.  It's something decided at the very beginning and usually doesn't change.  Of course anything can change if you have consensus, but that becomes harder and harder to do over time with a successful currency.  The unobtanium coin project has 1 coin.  The 42coin project has 42, there are some projects with ever expanding inflation that will never have an end to the number of coins they will have.  It honestly doesn't matter what number was used.  What matters is the inflation rate from rewards for mining or holding (proof of stake) or running nodes (proof of service).  These inflate the coin supply.  The coin supply may inflate forever, or reduce down to nothing.  Like Bitcoin, Dash reduces down to nearly nothing.  The intention is that the fees for services will eventually pay for the network.  

So the important things to understand, and unfortunately, I think most people don't, is that a single coins value is basically a % of the project.  So 1 Dash is currently 1/7,100,000 of the project.  1 morano is 1/14,000,000 or roughly worth 1/2 of the percentage of their project as what 1 Dash is worth.

Question is, does the number of coins mean there is a limit to it's use?  No, because coins are infinitely divisible.  Eventually, we might think of a Duff or a Satoshi as the main unit value, like we do the dollar.  We can easily say that hamburger costs 3.45 duffs.  Currently, there is an (ugly) standard of BTC mBTC uBTC and Satoshi as well as Dash mDash uDash and Duff.  Some of us would like to see better names, or re-assignment of names, but it's not important really.  The population will undoubtedly come up with something without us, such as in the past... buck, bread, clams, bills, etc...

Certainly, I believe that writing prices in 0.00000010 Dash will not happen, it's just too ugly.  We'll probably go by Duffs.  It's going to get weird again when we have to go more than 2 units below a duff, LOL.  But that would mean we have an economy participation of over10,000,000,000.  Maybe then, we'll call the units Saras after Mrs. Duffield, who is our first lady