Just like beauty, value lies in the eye of the beholder. You might think a post is absolute trash, not worth even opening, but someone may like it anyway more than stuff you find more valuable. Why? Why does anyone find anything beautiful? It's not an inherent quality in things, and so is value not inherent in things but relative to people's internal appreciation paradigm.

That's why evaluation sheets exist, to give people a list of criteria that things can be compared against to see if they meet the standard. Curators on Hive don't do this, of course (not most). Like @fredrikaa mentioned, some questions that can be asked are:

• Do they help promote Hive?
• Do they help engage?
• Do they provide user retention?

But in these, the terminal goal is "promote Hive and make people stay in it". Other curators could value different things and ask themselves different questions:

• Is the cover picture cute?
• Does it show any effort?
• Does it make me feel good or bad?

In the end, it's all based on how much they feel like giving, and humans are not the most rational, are we? :P