I've built successful products (https://chatgptwriter.ai and more) and here's what works for me:
Step 1: Offer your product for free. Free (and useful) products spread organically on internet. If people aren't using your product even when it's free, no amount of marketing will make it successful.
Step 2: If people are "consistently" using your free product over time, you can then offer additional value at a price or try any other pricing strategy.
Not all products can be offered for free, and that's okay. It's worth spending some money initially (if you can) because your primary goal is to reach Step 2.
Step 1 is useless for b2b products, and actually, a huge time waster. It will attract the very worst "customers" with near 0 chance of converting. Can work for b2c, however.
Step 1: Offer your product for free. Free (and useful) products spread organically on internet. If people aren't using your product even when it's free, no amount of marketing will make it successful.
Step 2: If people are "consistently" using your free product over time, you can then offer additional value at a price or try any other pricing strategy.
Not all products can be offered for free, and that's okay. It's worth spending some money initially (if you can) because your primary goal is to reach Step 2.