We tend to overestimate the effect of a technology in the short run and underestimate the effect in the long run.
In 1973, Roy Amara hired a team at Stanford Research Institute to investigate how scientists were using ARPANET, a precursor to the Internet that was only four years old at the time. They found that scientists were not only using the network for work but also for personal matters (one scientist realized he forgot his razor at an overseas conference and used ARPANET to request it back in 1973).
Amara’s Law is important to remember when it comes to the latest technological advancements (e.g., AI). But I also think it’s an excellent lesson for any goals. I’ll propose a more generic version with an added period:
We tend to overestimate what we can achieve in 6 months and underestimate what we can achieve in 18 months.
I’ve seen forms of this with all types of periods (1-10 years), but I believe the smallest and most surprising unit is 6-18 months. It’s arbitrary, but that’s my personal experience. Small enough to conceptualize but just large enough for our forecasting ability to break down. Anecdotally, many of the habits I’ve formed show initial results after ~6 months but don’t feel automatic until ~18 months. Plus, it tends to be aligned with business cycles (i.e., two to six quarters).