What are the rules of blogging and how are they applied? What is the purpose and the structure of a blog? How much is a blog worth? How does one gauge the worth of a blog or indeed its value? Pretty much the rules are publicize it and watch the income rolling in or not from advertising. I'll go into that more deeply though.
The basic rule for blogging structure wise is that the first paragraph should sum-up the entire blog entry so that it can be read simply and quickly before somebody decides whether or not to read the entire. This is something I very often omit, preferring to enter straight into the entry. It does however act as a guideline or a skeleton for the blog entries themselves, preventing them from straying off-path and becoming overlong. The final paragraph should be some form of conclusion based on what was said in the rest of the entry.
As for the other rules of blogging, good spelling and grammar, lack of profanity and blogging about something people want to read about are very important. As far as the latter point - there are so many people interested in so many things that if you find it interesting then somebody else probably will also. There are people that collect stamps, people that collect porcelain dolls and even people that collect antique condoms!
Publicizing a blog is one of the areas of greatest contention. There are some that say provide the content and label it well and the hits will come. There are others that say it has to be promoted. Usually those that say it has to be promoted are busy selling snake oil. To put it bluntly, if a black man was involved in intimate sexual relations with a white man in the middle of Main Street, Columbia South Carolina (a very racist, sexist area) then it would outrage many and they would talk about it for a week maybe two before they forgot all about it. It's the same with publicizing. Once the dark spiral of publicizing is entered, it's hard to get out of and leads only downward.
Once money is spent, be it on fake followers, fake hits, fake clicks etc, it's hard to stop spending money because there's always the thought that if just a little more was spent on a different snake oil salesman then riches would arrive. Even the definition of riches has a tendency to reduce to the point where the question is asked as to who to pay to reduce the outgoings of the site.
The worth or the value of a blog depends largely on your aims. If the aim is to make money then the value or the worth is the amount of money the blog generates. If the aim is entertainment for yourself or others then that is the worth of the blog. Both are dependent upon readers. There's no magic way to get readers. There's no magic bullet. Take JK Rowling's first Harry Potter book as an example. The first edition, nobody would touch so she self-published and had 300 copies printed. It was only when a publisher found a copy in a secondhand bookshop that it took off. He read it and was impressed and it all exploded from there. Some blogs never get many readers. Others get thousands. There's no trick or magic bullet. As long as the content is there, it's just dumb luck.
So, is it worth blogging? Only if it's worth it to you. If it fulfills your aims of income or entertainment then it is. If it fulfills neither then it's not.