People definitely undermine the ability of some teams to invest a lot of their efforts and time into making you believe that they are a legit project that will be here for a long time. They do this obviously for more profits. The more they pretend the more people will trust them and spread the word = more profit for them. This is why there are really no definitive tell-tale signs of a rug pull project.
That's exactly how Ponzi schemes work and many other scams follow this tactic. I've heard of a crypto investment scam where you gave the "investors an amount of money to invest for you, they'll deliver on their promise and give you the agreed amount within the agreed period. This would motivate you to invest more and also spread the good news. They even tell you about referral bonuses and would compel you to bring in more people, when they have gotten a reasonable amount, they'll disappear with the money.
Scams take different forms. Some are patient and take time while some just come to you right away. The more successful ones are the patient ones. They can last for years, picking up more potential victims along the way. They have people that can vouch for them. Most of these scams have people who can say "Look, I made this amount from this, it's legit", those people do not know they're doing the scammer's work for them.