A trigger can also be a passive customer behavior, such as not opening your last few emails, not logging in to use your service for a while, or downloading a product without downloading the tutorial or an important related resource. These types of drip campaigns can help re-engage customers who were moving through the customer lifecycle but have somehow gotten “stuck.”
That isn’t to say that sales-y promotions couldn’t ever create results—as marketing “gurus” have proved. The results just aren’t as good as they could be. Take the biggest gurus’ results—the ones they boast about—and calculate their conversion rates. Often their marketing is comparatively ineffective. They just have massive volume, so the sales numbers are impressive.