Blog owners do not always understand the reasons behind the mysterious blog security check (following "suspicious" / "unusual" activity account lock).
We see periodic complaints about deleted blogs and locked accounts - and the inconvenience involved, in Blogger Help Forum: Get Help with an Issue.
I get the security and all - but I don't get how a blog is just deleted.
This blog owner, like so many, does not understand how Blogger is trying to keep our blogs under our control - even after detection of "suspicious" / "unusual" activity.
Blog security check, if immediate and instantaneous, would not be noticed.
Blog security check is an art - not a science - and it takes time.
If blogs could be checked for hacking interference without delay, most owners would not complain. Unfortunately, examining blogs for hacking interference requires intense study - and most security experts do not work on weekends.
One unfortunate issue, about all of this, is that not all "suspicious" / "unusual" activity is malicious. Some of it is a simple result of people unable to use account / blog recovery - being innocently told to try every account name and password that can be remembered.
Owner delay, in requesting account unlock, contributes to security check delay.
In some cases, the locked account / deleted blogs may not be immediately discovered by the owner - and this may lengthen the security check process.
Not all blog owners publish - or even read - their blogs regularly. Nor do they accept the need to intentionally keep their account and blogs under their control.
Some owners are very casual about blog security - until a blog is successfully stolen.
Some #Blogger blog owners are not terribly impressed by the need to keep their blogs under their control, until a blog is stolen. The measures taken by Blogger / Google Security staff are considered mere annoyances.
We see too many problem reports, in Blogger Help Forum: Get Help with an Issue, about locked accounts and deleted blogs.
My Google account was suspended because of 'suspicious activities'. Last month, I realized that my two connected blogs, to that account, were also put offline!
Somebody else was unable to use the supplied account / blog recovery tools - and tried guessing what could not be remembered.
The first would be a blog owner, whose only mistake was having a Blogger account with a name similar to another account, owned by the second.
The second would be someone who could not remember her (his) account name / password, could not use account or password recovery, and who got well meaning advice.
Just do the best you can - try what may be your account name, and any passwords that you can remember!
One blog owner must suffer, because another cannot remember login details.
And owner #1 is suffering, because of owner #2. Owner #1 is now anxiously waiting for action by the security experts (with the blind queue of unknown length) to examine his blogs - and possibly, waiting while not knowing why.
Owner #1 may be seeing this - and not know why.
Password guessing may be necessary, in extreme cases - but it can cause misery - and owner #2 will never realise the pain caused to owner #1. Even if owner #2 recovers access to her / his blogs, innocent brute force attempts can cause account lock / blog security lock, to owner #1.
Protect yourself against the anguish, using Google 2-Step Verification.
The best way to protect against this sort of abuse is to use one or more Google Two Step Verification options. This will leave owner #2 seeing (for instance).
Insert your USB security key, and tap the lighted button.
And having no security key, owner #2 will simply have to try guessing a different account name. It may be an inconvenience (for owner #1), carrying a never used USB security key - but the one time it's needed (and available), it will make up for the inconvenience.
One #Blogger blog owner, unable to remember a necessary account name or password, may try guessing what cannot be remembered. Guessing an account name can leave one trying an account that somebody else owns - and can cause account lock and blog deletion for somebody who they will never know.