Well, this story illustrates the difference well. The Coles Notes: a man in Concord New Hamshire has made the news by painting the above message "NEVER EVER BUY BEHR PAINT" on the front of his home. He has done this as a form of public protest after he applied multiple coats of the brand's Cranberry-coloured paint and finding that his colonial style home's siding was still left looking streaky and pink.
In actual fact, this is a common problem with deep red paints, both inside and outside the house, and especially with cheaper ($40/g retail price or less) brands of paint. You see, if we were doing this house ourselves here in Ottawa, we would have used a high-quality, 100% acrylic paint like Benjamin Moore's self-priming Aura, which almost certainly would have covered in 2 coats - three coats max, even in this deep crimson tint.
So, you might be wondering... why's that? Well, high quality paints are composed of two main components: titanium dioxide (the "white" in the gallon and the same main ingredient as white glue, sunscreen and white-out), and pigments & colorants. As a general rule, the deeper/more intense the color, the more pigment and the less titanium dioxide is in the gallon.
So, the problem then is, when there is more volume of pigment in each gallon, and less high-hiding white ingredients, the result is often streaky coats. Many quality brands like Benjamin Moore have countered this problem by making self-priming lines that offer the same colour intensity, without that characteristic streakiness. This is achieved partly by the inclusion of pigments that are organic rather than inorganic in nature (for more on why this matters, and why some tints in general might be safer than others, take a look at this concise explanation on the Land of Color blog.)
In any case, department store brands like Home Depot's BEHR are often filled with additives like plastic to keep the cost low, without sacrificing that paint thickness that fools consumers into thinking their paint is top-quality (after all, titanium dioxide is not cheap.) And yet, because these plastic fillers are poor substitutes at best for the hiding power of titanium dioxide, deep colours mixed in these brands often cause many coverage issues... like those experienced by this frustrated, unfortunate soul in Concord.
So, the moral of the story is this: next time you're on the verge of a painting project, whether interior or exterior, and especially if the colour you've chosen could be considered deep and/or vibrant, remember that paying a little more per gallon for a high quality brand of paint is often well worth it if it saves you hours of labour for multiple coats. (The additional durability and washability of these high quality paints will then be just a welcome bonus.)
Or if you're unsure about the whole thing, of course, you could always entrust your project to a reputable, professional painting contractor in your area who can recommend a product that they know well and will stand behind (and hopefully warranty their work, like we do.)
