Good Domain Name does not contain?

Good Domain Name does not contain [letters,symbols,...etc]? why?

 

Are you talking about short domains? Long domains? For short domains there are a few letters which are considered 'premium' - high quality and others which are considered 'low quality' is that what you are talking about?

 

Both short and long domains.

 

Why are they good then? I suppose that all depends on the domain names you are using and even the one with dash can be mo valued then the one without dashes

 

Some time when you think to break single words into two parts, a single hyphen may worth to use.

 

Name cannot contain symbols. Only 26 letters, numbers and hyperns.
No fixed rule exist about what you asked. People prefer it short, memorable, no letter/number combination, no hyperns but that's not the rule.

If you go by logic you will ask yourself what would be nice domain for you?

 

I think they are difficult for SEO..plus its a general tendency of people to remember short and single word domain names..so its just that short single word domain names are worth much more