A half and last year taught us that WordPress security should not be dismissed by any means. Between 15% and 20% of the world's high traffic websites are powered by WordPress. The fact it is an Open Source platform and everybody has access to its Source Code makes it a prey for hackers.
If you do not have good protection on your site files can easily get lost. Some of those files may be saved in your computer and easily replaceable, but what about the rest of them? If you lose the first time to them where are you going to get them from again? Especially secure your wordpress website is very important. Long-term sites have a good deal of data and have created a number of documents. Recreating that all would be a nightmare, and not something any business owner would like to do.
Use strong passwords - Do what you can to use a strong password, alpha-numeric. Easy to remember passwords are also easy to guess!
Exploit Scanner goes seeking anything suspicious through the files on your website comment database and post tables. Additionally, it informs you for plugin names that are unusual. It doesn't remove anything, news it warns you.
As I (our fictitious Joe the Hacker) know, people have far too many usernames and passwords to remember. You have got Twitter, Facebook, your online banking, LinkedIn, two blog logins, FTP, internet hosting, etc. accounts that all come with logins and passwords you need to remember.
Change your password, or admin username and your WordPress password and collect and use other WordPress security tips to keep hackers out!