stockfish anaylsis depth

If you use Stockfish 8 to analyze your game, what search depth do you mostly use?  (and why?)

I have started to analyze my games using Stockfish 8 and find that I don't need to go beyond depth 1 or 2.  I sometimes looks into its ponder suggestion.  I mostly just use it to see if I missed any immediate, easy combinations.

I don't use an analysis function, where it looks at each move for a set amount of time or depth. I have the engine running so it's analyzing whatever position is on the board, then I go through the game on my own, stopping whenever the eval jumps, or at places I thought were interesting or confusing.

If it's a non-tactical situation and I was confused and I want something definitive from the engine, I'll have it show its top 3 picks and I might leave the room and come back in a few minutes. If it's just some tactical thing I missed, it only takes a second for it to show me.

If I'm in a hurry, I used 12-ply depth which only takes a couple minutes for a game.  If I want to really analyze my game, I set it to 20-ply, which takes about 70 seconds for each White or Black move.  I use Lucas Chess and Stockfish 8 64-bit and sometimes the longer ply makes a 1/2 pawn or more difference in how it evaluates certain moves.