Assumes that because something could happen, it is inevitable that it will happen.

Example

"There are many hackers that spread worms through the internet.
Therefore, if you use the internet without a firewall, it is inevitable
that you will be hacked sooner or later."

While using a firewall is a prudent and sensible measure, it is not
inevitable that a hacker will attack an unprotected computer. The
argument does have some backing logic but overstates the worst case scenario.

Form

This argument has the form: Possible P, Therefore, P

Treatment

The argument is mathematically flawed. There is always a chance that P will not occur, and therefore, no proof that P will occur given its probability.