For you, Mattu, I'll waive my usual fee:
The difficulty in converting freebie members to premium status lies in the fact that you give them everything they really need or even want for free.
Non-paying subscribers can create boards, post 18 messages daily on "stock" boards, and set up people and board Favorites lists. Basically, your ensuing sales pitch is that, for a fee, they can also scroll, search and socialize.
In essence, you have given them free appetizers, soup, and entrees. Now you're asking them to pay for dessert. The problem is that they're stuffed. They don't want any.
Without a doubt, you can take steps to marginally and perhaps significantly increase your conversion rates of new and recent members. (Perhaps you could select two from the many ideas that will be offered and conduct an A/B split over a three month period.)
But...
The best way to convert the freebie old guard is to offer them disincentives to remain non-paying. (Slash the daily post limit in half. No favorites. No iggies. No bread. No water.)
At present, you're giving away the store.
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