There are a lot of marketers out there that will tell you the goal should be to get as many people on your list as possible, and to just get that first sale. Authors will sometimes run crazy promotions (deep discounts on or free giveaways of their books, contests where they give away Kindles or other goodies to those who sign up, etc.), just to run up the numbers on their list, the rationale being that the cost of a Kindle, for example, would be more than earned back if even 1% of the 5,000 people who enter buy your book when you hit them with the sales pitch. Other authors will write a high volume of sloppy books, just to keep churning out material. And still other authors will purchase email lists from other sources, or pester their friends and family, or spend all of their social media time hocking their products, without giving any real thought to whether it's even a product those individuals would be interested in. Some people just don't like romance or sci-fi or horror, no matter who wrote it.

The trouble with this kind of strategy is that it's expensive and wasteful. Most mailing list services (AWeber, MailChimp, Active Campaign, etc.) have pricing tiers that require you to pay more money the more email addresses you have on your list. MailChimp for example, currently prices an unlimited plan for up to 1,000 email addresses at $15 per month, and an unlimited plan for up to 10,000 email addresses at $75 per month. So if you're indiscriminately adding any email address you can find, you may have a list that's ten times the size, but you're also paying an extra $60 per month ($720 per year!) for the privilege. And a 1% conversion rate on 10,000 addresses (100 people) is the exact same number of sales as a 10% conversion rate on 1,000 addresses.

There are also ancillary effects of having casual or unengaged fans. Those individuals are far more likely to review your work poorly, not promote (and maybe even criticize it) to other potential customers, and to ignore you or even remove themselves from your list if they don't see continued value in what you're providing.

At the beginning, finding true fans is going to be difficult. Especially if you're just publishing your first book or haven't spent time cultivating a following before. But the great thing about being an author is that your backlist can create passive income that will have impact and value far above and beyond any one new release, and true fans can help you find new true fans. Here's an example:

If you have 1,000 true fans when you sell your first book at $4, you earn $4,000. When you release your next book at $4, that's another $4,000. Fast forward a couple years and you're on book #5. Your 1,000 true fans are still going to earn you $4,000 for book #5. But let's say you pick up a new true fan at this point, quite possibly because one of those 1,000 friends told a friend with similar taste in material, "Have you read so-and-so's book yet? Oh, you have to. It's so great!" So sale #1,001 is someone who's never read your work before and absolutely loves it. What's he or she going to do? Well, a true fan wants to read everything you've written, so he or she probably goes back and buys your old books too if they become a true fan. Therefore, book #5 made you $4,004 dollars plus another $16 (your four previous books at $4 each).

And this is how true fans can really make an author a lot of money. As you write and publish more material, you create more of a backlist for your fans to find. Some self-published authors out there like Mark Dawson have even done an impressive amount of math to calculate the value of each new reader. For example, he's figured that for readers who read the first book in his series, a certain percentage (call it 5%) go on to read the next book in the series. And a certain percentage (call it 10%) who read both of the first two books go on to read the third. And a significantly increased percentage (call it 25%) go on to read the whole series if they've read the first three books. If he were to sell each of his books at that $4 price point, and he has 10 books in the series, that's a lot of potential revenue. He knows that if he can buy a Facebook ad that, say, convinces 200 people to buy the book, he'll likely make somewhere in the neighborhood of $844 and $872 ($800 from 200 people buying Book #1 + $40 from 10 people who buy Book #2 + $4 from the 1 person who buys Book #3 + a 25% chance of that 1 person also spending another $28 for Books #4-10) ... which means that even if he spent $100 on the ad itself, that's a tidy profit plus he has a reasonable shot at gaining an additional true fan who will buy Book #11 when it comes out!