Because general SEO companies don't write for clients, on the other hand, copywriting accounts for 60% of the success. After all, you cannot see a good SEO performance even they have done tech improvement (such as responsive web design, speed-up etc) and added a lot of backlinks. The SEO copywriter of EstherPoni is familiar with SEO, and full of experience. We can write articles understandable to both human and machine. So, it is natural to have the best SEO performance.