Yes Ford messed up a while back with their new V8 engines. They had a new spark plug made that was super long reach design to match their new V8 engine. Really really long reach. But some idiot engineer went with a two piece housing for the plug. After the plug has been in the engine for years (100,000 miles) the bottom half winds up stuck inside the hole. When you go to unscrew it the housing stays inside but the rest of the plug comes out. Sometimes the ceramic part breaks off and stays inside too. They do have a tool that is a threaded grabber kind of thing, but it may or may not work 100% of the time though. Thus worst case is that they have to pull the heads off to get the spark plug remains out. Obvously that is costly nowadays. I remember some Ford repair shops wanting a $1200 deposit per spark plug in advance before they try to change the plugs.

Fortunately, they did change the spark plug design to be a one piece design with a stronger bottom half, so that it doesn't come apart inside the spark plug hole. So the newest engines should not have the problem. But it really sucks if you have a older one though.