Trust, that is something that is almost never there. But, I will put some effort into a new coin if the dev has a known and proven track record, the team seems to want to succeed, there is a new algo or tech behind the coin, things like that. But I never trust these coin, never give them money. If a coin is going to make it, there are other ways to take part in the project and other ways to make money.
Yeah. Do your research. There will be several information you can gather about the team behind an altcoin and you have to be careful in deciding whether it's worth a risk or not. Join forums and threads. Valuable information would be picked up from there as well