title_body: What variables influence yield for a stovetop/moka pot?
upvoted_answer: Yield and the quality of the brew depends on how water is pushed through the grounds. Some things to consider:
  
  
  grind size: the finer the grind, the more pressure is needed to push water through. If you need to build more pressure, it may take longer to get to the same yield.
  grind consistency: this is related to grind size. If you have larger and smaller pieces in your ground coffee, you may get channelling. To get an idea of what happens, the smaller pieces may be lumped together needing relatively much pressure to push water through whereas the water can easily be pushed along the larger pieces. As such, an inconsistent grind can easily lead to an inconsistent brew (including yield).
  tamp pressure: do you tamp the grind (or do you level it out and push it with your fingers)? The more packed your grounds are, the more pressure is needed to push water through.
  Heat, how big you set your flame and how far you set your moka pot compared to the flame will influence how pressure builds. A very large flame with the moka pot directly above it will heat quickly and build pressure faster. This might result in a faster brew. You want to watch out though, you might end up heating the upper chamber too much making the first part of your brew burn making the whole thing needlessly bitter.