Steve Koger wrote a very insightful comment on one of my "Ask Derek" posts titled Required Experience to take the PMP. In the post, I was trying to assist someone who wants to be a good project manager. They want to get their PMP but they don't have the required experience to sit for the exam. I do want to be clear of three positions. [1] I don't believe you have to have a PMP to be a good project manager. [2] Though the certification may be used more and more as a marketing tool, just to get to the interview, I would hire the person not the credential. [3] I see more people attempting to game the system and get a PMP by going to boot camps and saying they have experience that they actually don't.
What is happening is an every increasing amount of non-qualified people becoming PMPs. Unfortunately, I don't see PMI taking any action to stop it.
This is what Steve wrote:
...while the PMP is more recognized worldwide, I’m not sure it carries as much weight as it used to… is there a marginalization occurring with the PMP credential?
I absolutely feel there is a marginalization occurring with the PMP credential. Because PMI is a “for profit” organization, they are motivated to get as many people certified as possible. I know they say they are trying to advance the industry of Project Management. I do believe that but I can’t ignore the marketing machine behind the credential. I’m worried there will soon be so many PMPs, the credential is becoming the next Dutch tulip.
I am of course comparing it to the Dutch tulip bulb market bubble of the 1600's. This was one of the most famous market bubbles of all time. Speculation drove the value of tulip bulbs to extremes. At the height of the market, the rarest tulip bulbs traded for as much as six times the average person's annual salary. (Source: 
Investopedia)
I see the PMP credential adoption being part supply and demand and part good marketing. Fact 1: Too many projects fail. Fact 2: Having a qualified and empower project manager at the project helm "could" lower the risk of a project failing. Assumption 1: If you have a PMP as your project manager, your project won't fail.
As with the economics of scarcity, the less there is of something where a demand exist, the greater the value. But scarcity and shortage are not the same thing. A shortage is when the demand exceeds the supply, usually meaning the price was too low and the market is not clearing. Scarcity always exists, but a shortage can be fixed. I feel the shortage of PMPs was fixed a few years ago. I see market conditions which indicate the PMP bubble is about to burst.
What I want to see is a limitation put on the number of PMPs certified per year. I want to see PMI go back and require not only a 4 hour exam but also require everyone pass a practical exam. I want to know that Project Managers are PMPs, not people collecting credentials. I want to see the stop of Paper PMPs.
I certainly don't have the answer. I want to do everything I can to help qualified people get the credential. But, that will mean nothing if there is a continued devaluation by people who merely pay a fee and pass a test.