Configurations are very useful when you want to show different positions in an assembly, to have similar parts with different sizes in a family, when you want to hide something specific in a drawing, etc… But like file names, the configurations names are used by SolidWorks as an identifier, as a reference. If that name is changed, an assembly or a drawing using it will throw an error.
Most of the time, people just name their configurations with that they do and it makes sense, I am not blaming anyone for that. And by default, SolidWorks will enter the same thing you entered for the Configuration name, in the Description field if you leave it blank.

The problem is that if instead of having the configuration named “Default”, you want to name it “Open”, you have to close everything that references this component’s configuration before being able to rename it. You also have to type the name twice because most likely the Description has to be renamed too. Once you are done, you reopen the referencing assembly or drawing and you get an error message. You will have to re-select the configuration with the new name.
To solve this issue, the idea is the same as the one discussed in the article about the Files Naming: it is to make the actual Configuration name an index independent of its Description by using an incremental number as name. This meaningless index is never modified, if you need to make a change you only alter the Description.
You can start with “0” or “1” and keep incrementing each time you add a new configuration.
If you are using SolidWorks 2016 or older you cannot reorder the configuration by dragging and dropping them. The configurations are sorted by ascending order and instead of reading the number as a whole it starts with the digits from the left. That means that “10” will be in between “1” and “2”. To avoid that you can add a leading zero to go up to to 99 which should be plenty but you can add two leading zero if you need more than 100 configurations…
Unfortunately, in that case, you might end up with with numbers not following each others if you use Derived Configurations.

Regardless of your SOlidWorks version, now you can rename your configuration’s Description with whatever you want, as many times as you want without breaking anything.
It is a good idea to include the first configuration name in your part or assembly templates so you don’t need to rename it all the time. Personally, I like to keep the “Default” as configuration Description for the first one and name it “0” but this is up to you. If you want to know more, take a look at the article about the Documents Templates.