because they feel lazy or lost interest to write. Not only like that, since they have another business to do in the real life, having blog is not priority except for people who live with their blog such as getting money from Blogging.
If you are typical of person who want to have instant blogging, you may use my trick. By managing and make scheduled posts in the blog, you dont have to feel hard to update. For example, if you want to feel free from updating blog for a month, you can post thirty posts first and then set your blog post time.
This is efficient and affordable way, your visitors would read new updates from your blog. You can go blog walking or leave it, its depend on you. The lack of this way put on your post theme. obviously, you cant post your life experience but you can still another topics such as article and opinion.
Finally no more reason to be less active on the blogging, since there is a feature to help you for giving the chances for updating your blog.So, lets update your blog.