If it's any consolation, I have been doing this for a year and am still learning. It just means you are alive
Anyway, I will share some data.
Firstly a lot depends on your PV.(Mod).
Most variable voltage variable wattage PVs have built in protection. So, personally I don't have any problems with unprotected.
BUT...
I also don't touch any battery (for my mod) that isn't a Panasonic or a Sanyo. I have overwhelming evidence that AW is extremely reliable, yet I haven't actually used any of his cells.
EDIT/ADD
Don't buy any of those batteries with a "fire" in their name. Junk, total junk.
Also recommend you get an Intellicharge i4 or i2. A good charger is very important. A multimeter is pretty important as well. Don't ever let your batteries go below 3 volts, most mods have an auto shut off at around 3 to 3.5 volts.
The biggest danger in unprotected batteries is attempting to use them in an unprotected mod, i.e. a mechanical.
Now if you are building your own coils ala Rebuildable atomizers, you don't want to make them under 1.25Ω or you can run into safety factors with regard to your battery.
There is much research to do. If you are just brand new and you have a VV/VW PV, the get a pair of the Panasonic CGR18650CH and you should be just fine.