Why certify?

Certifications are pursued by different professionals for different reasons. And there is always various arguments about the worthiness of certifications and what it achieves for an individual. So i just thought about doing a post on my point of view and whether it was useful.
For me doing a certification is motivating myself to prepare for something. For example when .NET came into the scenario i started to prepare for my MCSD on .NET since it was a very good way to make myself aware of all the nitty gritty details on .NET. I always viewed certifications as something that provides me the confidence and proves i have the minimum knowledge on using a particular technology or a product. But it isn't or never will be a replacement for experience. You have to view both as different aspects and view certifications as adding value to your experience.
So was certifications helpful to me. Yes a lot and it has motivated me enough to continue to keep myself upto date in the IT industry and technologies i am interested in.
Just my 2 cents...