What causes new development configuration versions?

Hi,

When connecting to a Development Configuration from NWDS I get the following message with title 'Outdated Develoment Configuration(s)'

---

The version 0000000022 of Development Configuration Internet Sales MOB_dev[0] (Version: 0000000020) is now available

For Updating of Development Configurations you have to remove and import them.

---

I've seen this message before and two weeks ago or so I did as the message said and went from version 0000000016 to 0000000020.

Two questions.

1. What causes these version changes? (I just want to understand)

2. what happens if I just keep on developing without switching to the other version?

(It takes a long time to remove the config and reimport the 5 or so projects i'm working on so i'd rather not do this on a bi-weekly basis)

Best regards, Marcel.