To ensure you may always have control of your blog you should assign roles carefully to the people who write for you:
They all have different levels of access to your blog.
If the primary admin changes job or is otherwise unavailable, you will still want to have access to the page. And anyone can have their WordPress account compromised. You might get hacked, and it is easy to forget your login – then blogs under your control are in jeopardy. Therefore you should give more than one person admin rights.
If possible you should require all require all admins to have 2-factor authentication (sometimes called login approval or verification) enabled on their WordPress account. This requires users to enter a code they receive via text message if WordPress doesn’t recognise the device they are logging in from. So, even if a hacker obtains their password, they still wouldn’t be able to access their WordPress account (and your blog) without the code.
We have more suggestions for securing your blog.