For me, I would say it is that results are not immediate. Back when I did SEO, I had trouble at times with convincing myself to keep going after a few weeks. I knew that the results would be great in the long term, but it isn't like hitting up a newsletter list or using PPC where you can see very quick results. Now, mostly doing consulting work, I see it with many clients, especially those who have no experience in the online world. I do my best to explain the process and how SEO provides long term payouts that are greater than you can get with almost any other payment method, but clients get discouraged when they don't fully understand it and are not seeing immediate returns. Humans want quick results by nature, in whatever we do. Knowing that what you are doing today in SEO won't pay off tonight, that you will have to wait for the results, is not an easy hurdle to get over for most people.
For me, it’s the back button because if your bounce rates are too high, it could signal the search engines that there is nothing substantial in your site.
I absolutely have to second what mhovingh said. It is ALL about patience and consistency. Don't give up and try not to check your SERP position too often. It will drive you crazy. I hear ya about the back button! B/c of that very reason, I am currently testing out YouTube videos on the front page of a few of my Amazon sites. I'm curious how much that will help visitors stay on my page longer.
as for me, my enemy is google algorithm. sometimes I don't understand at all how it works. why some of pages are indexed and other are not indexed...aaaaaaaa!!!it's awful))))
As mentioned earlier , the greatest issue faced is the time required for the the websites to rank for the chosen keywords. Especially when you start optimizing and are eagerly waiting for the improvements. Greater than all these is the upcoming probability of internet content censorship...
I don't think so. I do recommend the seo (a genuine way to analyze, measure the reputation, quality and value of a website)..