You have all talked interestingly but Miles2006, out this in thought that even those investing in a period of 4 years are still considered the short term investors because the period of their holding can not be compared to those investing ahead their retirements ba above 20 years or an average of 10 years.
Let's also understand the accumulation strategies of traders and investors are not the Same. Traders buys at any given time and sells at any cost while investors look out to buy at any price though but targets the dip and holds within estimated period of time while considering the market price before they can sell which ideally get those short term investors into fomo while long term investors remains focus because they don't intend to sell anytime soon.
We can call a person who invests for 4 years a short-term investor or not. For example, a person's portfolio depends on it. There are many people who buy 5-6 Bitcoins in a week and hold them for a long time. So, just because a person has invested for 4 years, we cannot call them a short-term investor. It is best to keep your portfolio for 2 to 3 circles.
If a person's goal is to build a portfolio of 2 BTC, if he can achieve his goal within 4 years and if he holds it for a long time, then we can never call him a short-term investor.