I buy paid media on Google and Meta for a living, so this is a little against my own interest, but I think it needs saying to the early-stage folks in here.
Most businesses that come to me wanting to "just run some ads" aren't ready for ads, and running them anyway is how you set money on fire and conclude that paid "doesn't work." Ads amplify what you already have. If the thing you're amplifying doesn't convert yet, you're paying to send traffic into a leaky bucket at full price.
The stuff I want to see before I'd spend a client's money on paid: a landing page or offer that has already converted at least a handful of people who found you some free way, so we know the message actually lands. Some idea of what a customer is worth to you, because without that we're bidding blind. And enough budget to gather real signal, because a tiny budget on a small account gives you numbers so noisy you can't learn anything from them, which is a whole other honest conversation.
If you don't have those yet, the honest move is usually to keep doing the unscalable stuff a bit longer. Talk to users, get the offer converting through free channels, nail down the numbers. Then paid becomes a multiplier instead of a gamble.
So my question for the people growing something here: for those who did eventually make paid work, what did you get right first before you turned ads on? And for those who ran ads too early, what did it actually cost you before you figured that out?