[strken]

There's an argument I've seen - no idea whether it's correct - that users acclimatise to new advertising technology and eventually regress back to the mean. I suppose this would mean that newer and more invasive ads cause a spike in consumer spending, which drops over time until the next innovation.

[daveFNbuck]

I've never seen someone make that argument for better targeting, which is what they're saying cookies enable. You're not going to acclimate to being more interested in the ads you're seeing.

[TeMPOraL]

The argument for better targeting is simple: targeting works (whether directly or just through being a novelty), and those who engage in it get ahead of those who don't.

The argument for getting used to ads is mostly psychology/neuroscience.