A list of things I was wrong about.
Not in order
Not exhaustive
With major recency bias
Will add more as I remember them and uncover new ones

The idea is that writing these helps me think about why they happened in the first place, and reminds me of the types of mistakes I tend to do

In April 2020 I thought many countries would crush corona in 6-8 weeks

Assumption: The world can crush corona out of existence in 6-8 weeks with strong lock-downs.
Result:
Mistake/assumptions (with Hindsight): I assumed that since the virus has 2 week incubation period, it would take 4 weeks to find out most cases.
Alleviating factor: It was clear that countries that kept most public transportation open, and had ultra-compact housing (worker housing) that it would be impossible to control.

Stock Markets and Companies

Since 2016 I have been thinking the US equities market has been overvalued. Until this writing in September 2021 the bull run is still going strong.

Airbnb

After several incredibly disappointing experiences on ABNB as a guest AND as a host in 2017/2018 and hearing many other anecdotes I became quite skeptical of Airbnbs success. I just used it again in the summer of 2021 and it was ok, but more importantly glad I didn’t short it (thankfully it was private) as it has gone up 4x in value from the 31 B in valuation in 2017.

Startup Investing

Biggest mistake in startup investing was getting excited about startups because “there’s so much I can help them with” Ideally invest in ones that don’t need the help.
Other mistake was investing in founders that were always asking for permission/approval/endorsement etc.
Others (mistakes/near misses):
- Shaky founding teams/dynamics
- Doing it for the money/”cool factor”

Crypto

On 3 separate Crypto cycles I bought in relatively early and exited also too early. That said just reading a book “The Zurich Axioms” that teaches not to regret cashing in early in trades as usually you are more likely to get burned if you get too greedy and hold on for more gains. (Caveat this doesn’t apply to investments you are intending from the start to hold for the long term).