Here is a good source to decide which altcoin to invest in. I would never buy a dead altcoin with no development except Doge. Doge is unique and will be successful without much development.

Source:
https://twitter.com/el33th4xor/status/1068856384983363585?s=21dead alts are:
- Verge
- Holochain
- Bitcoin Private
- Pundi X
- Poet
- Decentraland (MANA)
Of course everyone who can read and see will invest in an active project, but not a few of the many investors who fail at the stage of selecting the project to invest. There are also investors who lose their assets after investing due to severe panic during a bear market, so they sell at a bad time.
I think even though you have chosen an investment in a good project, if you still have an impatient attitude, and easily panic, you will still experience setbacks in investing