Starwood already had a reasonably generous promotion for its winter quarter, with double points on all stays of two nights or more at all properties and a bonus 250 points per stay at select properties through April 30 (register by April 10). Just offering this promotion at all of its properties is a good step. In past years I’ve seen promotions that exclude every property in some cities, from the Four Points to the W.
However, Starwood seems to think it wasn’t generous enough. It is now tempting very frequent guests with the chance to earn up to 10,000 additional points. You can get 2,500 bonus points when you complete 15 nights and an additional 7,500 points (10,000 total) when you complete a total of 25 nights. As far as I can tell these can include individual nights (not just the two-night stays that are required for the original promotion).
Someone who stays 25 nights by April 30 is well on their way toward Platinum status for the year, so Starwood is clearly targeting its most frequent customers — or people who might become frequent customers if suitably enticed. This may be because they know Hyatt is poaching a lot of Platinum members by offering them Gold Passport Diamond status. Or it could be because the hotel industry is in a downward cycle (Goldman Sachs recently downgraded Hyatt, but cited the entire industry).