Writing a blog about a topic you are not a complete expert in?

The term "expert" can be wide, but, what do you honestly think, how much "expertise" is necessary in a certain topic for you to run a blog or website about it?
How much previous knowledge do you need to have? Is it a good idea too learn a long the way, and do your research while you already start?
If you start a blog, for example, and start writing a certain article, but you don't know EVERYTHING about the topic and need to do some research to get enough quality for your posts

 

NO one will EVER know EVERYTHING about ANY topic. So, jump in, get your feet wet, and learn as you blog.

 

No one can claim that he is 100% expert in any specific sector. No matter how long he has been working in that role.
So, if you want to make blog in any specific topic, you should not necessarily be expert. But you have to occupy basic understanding of your desired topic. I use to write blog. Before start writing on a topic, I searched on google a lot of related content and try to get an idea from those article. Then I use my own knowledge and acquired idea from google to write a content or article. You can try this method.
Thank you.

 

So many questions within your question.

Like @sarahk said, it depends on niche
Some niche will not require you to have any kind of expertise, will just require a good writing style that can engage readers.
For example, TV show / movie review niche.
You simply have to watch the movie, or a TV show and write your opinions about it.
Nobody can question you. Its all your personal opinion. No expertise needed.

Then there are some niche where you must know a lot about the working of things before doing anything.
Like if you are teaching music on your blog, via videos etc.
You need to know a lot yourself.

Then there are more serious niche,, like medical advice

What do you want to blog about?

Personally in my opinion, its already difficult to write a blog about the subject you are good at,
because of the frequency of posting alone,
on top of that if you are deciding to start a blog where you do not know much, then its pretty much going nowhere anytime soon.
You can keep a log of everything you are yourself learning and hope that someone else will also find it useful...
But even here, you will need some kind of passion to learn about that niche.
Generally, the passion fades away in a couple of months, and now you got a 20 page blog just sitting there, not knowing what to do with it.

 

I have business, but I can't say for sure I am an expert in it. Yes, I have enough knowledge to provide some service but I also try to improve my skills every day. That's the key

 

like mariopepper one needs to improve their knowledge. I also ask experts to help or comment my posts where I lack of knowledge