Do the Italian bottom brackets unscrew itself when in use?

Italian BBs as well as French BBs use right handed threads on the right fixed cup side, instead of the left hand threads used in English/ISO BBs. In theory, this makes them more likely to loosen with use, however, if properly tightened they should remain tight.

Just grease the threads with olive oil and melt some mozarella around the edges of the cups.

You forgot the tomato sauce and anchovies

I reckon TejanoTrackie has this one nailed - if anyone should know, he would.

Had this happen during a century. Not fun as I don't routinely carry a bottom bracket tool. Fortunately found a bike shop not too far off.

Mozzarella sounds like a good call. Failing that Loctite.

When you initially install it, keep an eye on it. Checking that the lockring maintains its adjustment after every ride will tell you whether it is adjusted correctly. I would do this for at least a couple weeks of riding days. In my experience locktite is sometimes necessary and sometimes not, only resort to using it if you have problems with a grease install.

It was loose. I could turn it with my fingers. It did looked odd yesterday. I went ahead and tighten it. Thanks everyone

As TejanoTrackie said, if installed properly it won't cause you any problems. I've ridden to the moon on bikes with Italian bottom brackets and I've never had an issue.

I never thought about it, but do cartridge BBs have the same precession problem that loose ball BBs have?

The bearings aren't contacting a cup that's threaded into the frame...

For external BBs you're back at square one, I'm talking about square taper/octalink/isis/whatever cartridge bbs here.

Well, there still is bearing precession that's wanting to turn the whole cartridge shell, but it's causing the adjustable threaded cup/ring to tighten, so the fixed cup isn't going anywhere, since the cartridge shell is rigid.