Most of the best strains and genetics in the world, are ones the average person interested in Marijuana has never heard of. There are many amazing breeders all around the world, that never bother entering cups or publicizing their genetics They breed for fun, friends and their local community. There are also smaller breeders, that breed and sell their genetics, but simply don't have the financial backing or marketing required to blow up all over the world.
Seeds, and genetics are like any other industry today. You need great marketing, and lots of capital. Without these, your company will never be able to compete on a massive scale, no matter how good your products are.
Lets use Headphones as an example. Beats Headphones by Monster are the most sold Headphones in the world right now. Yet they are garbage. Other companies, like Grado's or AKG, offer better headphones for less than half the cost. If you go to sites like Head-fi, a community of people who have a passion for audio and headphones, they wouldn't put any of the Beats model headphones in their top 100. Yet you see celebrities and the average person walking around with them every single day. Why? marketing. They don't know enough, and are not willing to learn enough, to realize although Beats may sound good, there are dozens and dozens of other Headphones that sound better, look better and are less money.
Another factor you need to account for is the legal status of growing, shipping and producing Marijuana and seeds. It requires not only a large operation, but a legal operation to compete with breeders on a large scale. A huge majority of growers, who have been growing for decades, do not live in an area of the world where it's legal. They may also not have the resources or motivation to move somewhere like Colorado, California, Amsterdam and so forth. Sub-Cool has been growing for over 25 years, and how long as TGA been around?
Many other breeders lack the logistics and care to ever enter a cup. Like Esko. They breed for fun, they breed from passion and they have no interest in awards. Many companies can also not easily ship their products all around the world. It's illegal to import and export Marijuana and Marijuana seeds. Even if you have a state or province level legal status, it's still federally illegal in America, and simply not allowed by the Canadian government as it's suppose to be a medicine, not a "hobby". Do you really think Canada doesn't have some insane genetics and breeders? Most Americans have never heard of Jean-Guy (John Doe in English), but it's one of the best strains I have ever tried in many entire life.
Cannabis Cups are also about more than just genetics. As pointed out in this thread already, it's far more about how it's grown. You can have the best genetics in the world, but if you grow it like 80 percent of people on this website, it will be thrown in the garbage by the judges long before it's smoked. You can take the greatest strain ever made, but if it's grown badly, it will be worse than the most average strain that has been grown correctly.
A lot of breeding companies are busy just trying to not get raided and keep it a profitable business. It takes massive amounts of work to enter a cup, move your product, set up hotels, bring samples, give out swag, all while having crops you need to sell to patients back at home that could all die since you are away at a cup.
There are also many suggestions that the Cannabis Cups are very biased, and many judges just give awards to friends, or people who have given them the most samples.
The entire way Cannabis Cups work is terrible, and gives people living in certain areas a huge advantage. It's not like movies, where you put your movie out, and a panel of esteemed judges decide if you deserve an Oscar nomination. As a breeder, you put your product out and nothing happens. Instead, you have to grow it, market it, find a Cannabis Cup, apply to enter the cup, smuggle your marijuana across borders or state lines (illegal), hand out free samples, give out swag, make a big scene to get noticed, then hope your sample for the judges is still in great condition, then hand it to a judge that is already stoned and can't tell the fucking difference. A judge who has no real qualification, then after all that, hope he likes it.
The point is this. Just because a strain or genetic is popular, or the company had a large enough staff and deep enough pockets to enter and win a cup, doesn't mean it's good, or the best. Many smaller breeders are making some of the best stuff in the entire world, and a huge majority of people have never heard about it because it wasn't in some terrible rap song.