The color degradation is dependent on the used print method and used colors. Many of us have put a hefty sum of money to Adobe's software because it can acceptably predict the color degradation in many print processes. CMYK printing has remarkably smaller color range (=gamut) than computer screens, so it's very easy to make an image which seems dead and flat, when one prints it with CMYK printer.
see the next screenshot:
In the left is your original image (or what's left after 2 uploadings to Imgur) In the right there's a version which has been converted to CMYK profile Euroscale Uncoated (=a random selection) and back to sRGB. As we see, the simulated CMYK process made it flatter, but only blue has suffered substantially. The image is obviously well prepared for CMYK printing. See in the next example, how much not so well prepared images easily suffer:
In the left there's a bright RGB design. In the right there's Photoshop's prediction how it would come through CMYK printing, which uses color profile =Euroscale Uncoated.
Your photo of the printed phone cover doesn't reliably reveal very much things about the actual printing. The photo is unsharp. Nobody can be sure how blurry is the printing. It has obviously got all vibrancy and general sweetness boosting that low cost cameras insert without asking and many Photoshop users add themselves, if the camera for some reason doesn't add it enough. Finally the light is non uniform and there's bad glosses in the right.
One thing is clear. CMYK printing on black is useless. It needs a white background. Possiblities to get the apparent black base color:
A white underprint on areas where the printer had thought it pays off. Between those areas there's black plastics as is or black ink.
White cover with black edges, print only the flat area
3.The print is a thin transfer foil which is printed elsewhere and pressed or vacuum sucked to the phone cover with special equipment
- Print with pigment colors which do not need white underlay. (I don't believe it's the case, because the printing would be complex)
Let's assume your phone cover is made with option 1. You can build a stack into Photoshop which generate some errors to an image:
The top layer has a grey circle and some painted low opacity white to simulate washiness. Below it there's a complex group of layers. The uppermost group level is converted to smart layer to be able to insert adjustable blur for unsharpness as "smart filter" This is Photoshop's way to non-destructive filterings.
The content of the smart object is taken under editing. It reveals the rest. There's also grouping:
Group "white underlay simulation" desaturates a copy of the image. The desaturation result its softly tresholded with a steep curve to make white those areas, which are bright enough to earn white underlay. The group has blending mode multiply, so it actually makes dark areas of the image full black.
Those areas which are not blackened, get contrast lift and color distortion. Contrast lift with curves is adjusted to cause overexposure-like clipping. Hue&Saturation layer affects to reds shifting them towards orange and reducing saturation.
I have no idea of the used CMYK printing, so I didn't convert the image at first to CMYK and back. You should do it. As well you can keep it in RGB mode and have View > Proof colors = ON and set a proper proof mode (ask your printer for it)
If you want to check this monster, you can get it from here: https://www.dropbox.com/s/us0hllpmbmvan1h/Messi.psd?dl=0 Right click the group in the layers panel to get a possiblity to see and edit the inner levels.
You must find the proper settings, it's impossible to decide them here with a single not so high quality image of a phone cover.
If you do not print the covers by yourself, I recommend you to ask the printer for a proper preview method.