This does not cause a problem for the majority as it is not extremely important to get a 100% onscreen to print match however if you are set on a particular onscreen colour we can except no responsibility for your print items and suggest you get a print proof and talk to your printer.
Colours on screen can differ quite considerably than the finished professional print product. Your design will look different on screen, different when you print from your inkjet printer, different if you receive a digital proof and different when litho printing. Colours may even change from print firm to print firm. If you have specific pantone or CMYK colour references we are more than happy to use and is the most secure way of getting a colour of your choice. Monitor settings and quality can also contribute to colour variations, your design can look different from one machine to another.