Question: As stated from the questions title:

**What does 'beta' state of a SE site actually imply?**

Could someone elaborate, which restrictions or drawbacks we should expect from a *'beta'* SE site?  

I could have well been missing something, that's already been answered, or is an easy to find policies concept.

Answer: 
Also, in addition to [Troyen's great answer](https://meta.stackexchange.com/a/239406/184589), another significant difference is that on Beta sites there are no moderator elections.

The moderators are instead hand-picked by the Community Managers from the pool of members that contribute with valuable content and demonstrate constant participation.
Although this doesn't answer your question specifically, you can glean a lot about how sites are created and grow in Area 51. Some die on the vine too.

[StackExchange Area 51](http://area51.stackexchange.com)