The U.S. Army has begun issuing its new combat uniforms featuring a new and improved camouflage pattern. This is yet another effort to deal with troop complaints about the shortcomings of earlier camouflage patterns. Back in 2012 the army has decided to scrap its current digital pattern camouflage combat uniforms and replace them with the more effective (according to the troops), but more expensive, MultiCam. Actually, MultiCam itself was not used but a pattern selected for the new uniforms, but one based on MultiCam. This variant is called Scorpion W2 and the army gave it another, official, name; Operational Camouflage Pattern (OCP). So if you hear someone talking about the new uniform being Scorpion W2 or MultiCam they are not entirely wrong. But the final, official term is OCP.
Since 2001 both the army and marines adopted new, digital camouflage pattern field uniforms. But in Afghanistan U.S. soldiers noted that the marine digital uniforms (called MARPAT, for Marine Pattern) were superior to the army UCP (Universal Camouflage Pattern). Both UCP and MARPAT were introduced at the same time (2002). From the beginning there was growing dissatisfaction with UCP, and it became a major issue because all the infantry have access to the Internet, where the constant clamor for something better than UCP eventually forced the army to do something.
This is ironic because UCP itself was another variant of MARPAT but a poor one, at least according to soldiers in UCP who encountered marines wearing MARPAT. Even more ironic is that MARPAT is based on research originally done by the army. Thus some of the resistance to copying MARPAT is admitting the marines took the same research on digital camouflage and produced a superior pattern for combat uniforms.
The pattern used for UCP showed great promise initially, but the way it was implemented contributed to its failure. To understand how this happened you have to know something about digital camouflage pattern. All them, like UCP use "pixels" (little square or round spots of color, like you will find on your computer monitor if you look very closely), instead of just splotches of different colors. Naturally, this was called "digital camouflage." This pattern proved considerably more effective at hiding troops than older methods. For example, in tests, it was found that soldiers wearing digital pattern uniforms were 50 percent more likely to escape detection by other troops, than if they were wearing standard green uniforms. What made the digital pattern work was the way the human brain processed information. The small "pixels" of color on the cloth makes the human brain see vegetation and terrain, not people. One could provide a more technical explanation but the "brain processing" one pretty much says it all. Another advantage of the digital patterns is that they can also fool troops using night vision scopes. American troops are increasingly running up against opponents who have night vision optics, so wearing a camouflage pattern that looks like vegetation to someone with a night scope is useful.
Apparently what happened to UCP was that senior army procurement officials changed the original UCP design because it looked too similar to the pattern the marines had selected. These changes made UCP less effective as camouflage. This contributed to the resistance, at the highest levels, to even admitting the UCP was not up to the job. After the eventual rejection of UCP in 2002 the easiest thing for the army to do was to just adopt MARPAT. The marines didn't like this but they really couldn't stop it. Instead the army went back to the original source for both MARPAT and UCP; MultiCam. This was adopted by SOCOM (special operations command) in 2002 after their commandos had second thoughts about UCP. SOCOM went looking for something new and found another digital pattern called MultiCam (cleverly designed to hide troops in many different environments). Many in the army preferred this one but MultiCam was about three times more expensive than UCP.
SOCOM operators have their own budget and had many of their guys out in the field wearing MultiCam, rather than UCP. That proved the superiority of MultiCam to most troops. SOCOM has always had a larger budget, per capita, than the rest of the army, and its operators have a lot of discretion to use whatever weapons or gear they thought best for the job. Apparently, on some jobs, MultiCam was considered more suitable than UCP and came to be used most of the time.
The army tried both MARPAT and MultiCam in Afghanistan and found MultiCam more effective and popular. The fact that MultiCam was a favorite with SOCOM was a deciding factor. So, after over more than a decade of use, UCP gets replaced by its more expensive and, at least in Afghanistan, much more effective competitor, MultiCam, or, to be precise, a variant of MultiCam called Scorpion W2 but officially known as OCP.