There’s a famous saying: “Good advertising is a tax you pay when you have a bad product.”
If you have a good product (or service), you shouldn’t need to advertise, as your customers will do your ‘selling’ for you (also known as word-of-mouth marketing).
If your product or service is remarkable i.e. worthy of remark, then people will tell other people about it. In practice, this means that you have to ensure that what you sell is good. Really good. And then use face-to-face networking and social media to get people talking and sharing recommendations with each other. Maybe they are already discussing your industry, your business or you? Either way, you need to be part of the conversation. And there are certain places (both online and offline) where you just need to see and be seen.
The opposite of remarkable is unremarkable. Which leads to another famous quote: “There’s only one thing worse than being talked about, and that’s not being talked about.”