Try to understand the science behind color and its effect on your business. People may think having best product and huge marketing exposure can bring loads of sales.
Yes, they can. But, when the market is filled with competition you can't expect to run a successful business without having a brandable logo color.
Like your business name shows your business, its logo color will help to build trust among your customers. Reports say that color does impact on customer's feelings. Psychology report by a marketing company concludes that people make the judgment about a product in subconscious mind within 90 seconds, and majority people consider color for assessment.
Before you run your visual mind to select a color let me give few examples.
Facebook used blue color because it stands for trust, stability and intelligence. Blue is man's color and it stimulates calming effect.
Red color exhibits energy, war and passion. It also used to make quick decisions; this is why most designers use red on buy button.
Pinterest.com, most of its users is women. So, accordingly they concentrated on their fancy logo and related color, which stands for love.
Green color used by eco-friendly companies, whereas dark green is associated with money.
You can get more about color and their meaning here.
Now, you know what your company stands for and what its relevant colors are. Select 2 colors first, and they should work with each other. Mean when you use both of them they should look good. Blue and green, red and yellow are good combination.
This color will be your brand's color. You shouldn't change this color with different marketing strategies. Every tactic and poster will have same colors.
Here is an infographics showing psychology of color.