On April 24, 2012 many started to see that Google has started to penalize companies that are buying links for the purpose of passing off the rank. The Google Update was called Penguin. Since then, there have been several different Penguin/Panda updates rolled out by Google. SEM has, however, nothing to do with link buying and focuses on organic SEO and PPC management. As of October 20, 2014 Google has released three official revisions of their Penguin Update.
As you can see by the example above, organic marketing tactics are natural, authentic, and value-based. The benefits that businesses reap from these tactics are cultivated over longer periods of time, ultimately helping you build a brand that customers want to visit regularly. And although you’re doing less “pushing” with organic marketing, when done right you can still generate a steady stream of loyal traffic. Remember, this is about building high-value brand equity and industry authority with your customers. You’re not just attempting to drive sales here; you’re working hard to engage and educate your target audiences.
Unless you’re eBay or Amazon, PPC can prove to be an expensive affair. You may initially not feel the pinch of it, but overtime, the costs keep growing. If you’re not doing enough testing with your ads, you may end up losing a chunk of your ad budget without any great returns. Simply focusing on the wrong keywords or markets can make a huge dent in your wallet if you are lenient with your ad budget.
I agree with the point that a small or medium-sized business will have limits for budget and resources in generating brand search, but I wouldn't say that stops them from potentially producing huge growth there if they do something interesting/innovative etc. I can think of quite a few small to medium sized brands that have more name recognition than larger companies in their space. The challenge is that many of those brands are led by people who are very good at generating marketing and publicity - it's harder for small brands to be able to afford to pay for a top level consultant or agency.
Organic traffic, on the other hand, are those visits which are tracked by another entity — usually because they have arrived through search engines — but also from other sources. Hubspot’s definition emphasizes the term “non-paid visits,” because paid search ads are considered a category of their own. But this is where the lines between direct and organic start to get little blurry.
Your keyword research will determine whether or not your search optimization effort will be a success or a failure. Many businesses make the mistake of basing their keywords on just the search volume. This often leads to attempting to rank for keywords that are very difficult and costly to move up, or even keywords that aren’t “buyer” keywords and just send useless traffic to the website.
Organic is what people are looking for; the rest of these simply put things in front of people who may or may not be seeking what you offer. We know that approximately X number of people are looking for Y every day. So if we can get on front of those people, we have a much greater opportunity to create long-term relationships and increase our overall ROI.