One of the top webpages in the world are search engines. I believe it is so, because a high quality search engines save people a lot of time and help them find what they need. When it comes to your website it is also important to allow your visitors to use the search option and allow them to browse through your site this way. This is especially important if your site accumulated a lot of posts, since finding them manually would take too much time. By integrating search into your site you allow people more freedom exploring your blog, but you also make your site look more professional.