raniE
Adventurer
I disagree. The current edition was bringing in tons of players. A lot of them would eventually buy at least the PHB, and possibly more of the core books. The core books are always the core, they're what makes you money. The same is true for as far as I know every game company.WOTC benefits but I believe it waxes and wanes heavily and cant be relied on unless you reset the system (new edition) every 10 years.
Once an edition get long in the tooth, WOTC runs out of widely marketable product. WOTC can't compete with 3PPs for niche products.