title_body: What mechanism in premium manual coffee grinders allows coffee grounds to come out uniform?
upvoted_answer: The biggest &quot;technology&quot; that can affect a coffee grinder is the burr set (Aka the bit that actually grinds the coffee). With the burr set, there's a lot of factors like
  
  The material of the burr set (Different types of Steel, Ceramic etc)
  The pattern of the cutting teeth is usually specific to each burr set maker.
  How fine/coarse you can adjust the grind size and the level of adjustability between these two points (stepless / stepped)
  
  While these are the &quot;main&quot; factors, there are other secondary factors like the driving mechanism that makes the actual burr set turn and even just how well the entire coffee grinder is built-in general (like the materials used and body).