- You might end up holding dead coins if the project gets abandoned
This is so true. When an investor doesn't really care about the money he invested and he's very confident. He won't have that urge to know the updates of that coin.
- You might miss swaps and end up holding worthless tokens
- Delisting of coin/token and you miss the withdraw period (in case you store coins/tokens on exchanges)
As it becomes abandoned, expect that it will become worthless.