MVP. This is pre-pmf where nothing is certain and you just want to launch features to your users.
Time horizon to consider: don’t think, just get the feature done.
Stage 2
After some sort of PMF. You start seeing enough traffic where your design decisions start mattering, and you want to build out a system that can hold up longer term.
Time horizon to consider: 6-12 months. Still you shouldn’t think too far into the future, just make sure the designs you build can last you 6-12 months.
Stage 3: Actual scale.
Time horizon to consider: 1.5+ years
You’re actually scaling and product / requirements are more or less set. Can’t say much, I haven’t been here yet.