Selling anything is about transference of TRUST, which comes from awareness and frequent exposures over time.
Ever hear the term "Building a Friendship?" Building is a key word. When you first meet someone there are certain things you don't do, don't ask. It would simply be too odd. But over time once you know someone you can ask for a favor because you are known to be responsible with that favor to the friends with who you have BUILT trust.
Those unfamiliar with advertising want instant results (who doesn't?)... But the same principals of friendship apply to advertising. You have to build one brick on top of another. Eventually you are trusted.
When we first started we received some advertising resistance. People said they wanted to "watch" us. What they are really saying is we want to see if you're trustworthy. See if you continue to produce a quality product, etc. Same holds true for advertising.
If you're targeting a new group of people who do not have the advantage of knowing about you and your brand.... you have to build that trust before they will confide in you with their dollars. It's rare someone will send a check for thousands or tens of thousands of dollars unless they can feel comfortable that they will receive what they purchased and it will be authentic. That comes with trust. Trust can come through the references of others (good reason to use testimonials or quotes from known people in your marketing to new people).
It's important to remember that TRUST IS A PROCESS. The reason advertising specialists recommend CAMPAIGNS instead of single ads is that ONGOING visibility helps people become more comfortable with you. Just like a new friend... each time you get together you trust them a little more. Eventually you're real friends. Same with ads.
Can you speed the process? Somewhat... through the HALO EFFECT of others (testimonials or known spokesmen). Design quality and association with GREAT art also helps. Also size of ad sends a message of confidence. Ever see a spread from a gallery which is six or eight full pages in a row? It says "Wow! These people must be big if they can afford this." Of course TWO pages together send a similar impression. Full pages send an impression over fractional sizes. Its human psychology 101. Still FREQUENCY and CONSISTENCY is critical. If you're there...then you're not (and the potential customer is paying attention) it raises question. Also it reinforces your messages. It’s a cumulative effect, not a single ad but the impressions of multiple ads. Author Roy Williams says that people LOOSE impressions over time and if you are away too long you have to start from scratch.
Trust is a building process.