This is a good warning which I see as a good advice. No matter what the project is promising it is wise to participate with spare funds so that In case of unfortunate events one can still move on. In time past this crypto space has taught us vital lesson which one can't forget so soon. There have been many projects which looked legit only to defraud users, there are also others which had a good public sale but didn't list on any exchange, while there are others which list and the team abandoned the project. So with all these experiences, your warning is very important and accurate; make your research on any project but always invest what you can afford to lose.