This is why. You can't hold on to people forever, despite the all-important stickiness factor. People actually appreciate when a website doesn't try to convince them they needn't go anywhere ever again. Keeping your content mercifully short serves many masters. It de-stresses your reader and makes it easier on you.
Tips are the rage on the Net.
Choose not to churn and burn. This means you've got to have a very aggressive acquisition program. If you don't, you'll find your subscriber database will actually decrease every time you publish, since the bounced emails plus unsubs can easily outnumber new subscribers. I've noticed it's become harder to acquire new subscribers over the years. BTW, completion rates aren't what they used to be either, when it comes to filling out those online subscription forms.