"Be thoughtful about what you're giving away for free and why. Freemium and free trials are all the rage, and virtually every digital news organization has some content that's not behind the paywall. Great. But make sure you understand the return on this investment. A free trial is a taste of something to prove it's as good as you said and to help someone new to understand what it 'tastes like.' But once they've tasted, they don't need to taste it again. Too many readers game the system, clearing cookies and rotating through devices and news sources each month to avoid paying."
That quote comes from best-selling author and speaker Robbie Kellman Baxter—she even keynoted a past SIPA Conference—in an article she wrote for the site What's New in Publishing titled What Publishers Can Learn From Other Sectors.