Lipo batteries are made up of more than one cell.
2s=2 cells 3s=3 cells and so on.
When running and or charging they can get to different voltages.
So say you run your truck/car and it gets to low voltage cut off.
Well for a 2s lipo it should cut out at 3.2 volts per cell 2 cells=6.4 volts
OK now say one cell gets down to 3.0 and the other is at 3.4
Over time without ballancing if your cells get too far out of ballance, cell #1 couls still be at 4.0 volts and cell #2 is at 2.4 volts.
Now cell #2 is below the voltage it needs to stay working and LVC is still kicking in.
Your pack will now puff and be junk because the #2 cell got below the voltage needed to be a working cell and pack will be junk.

OK now the other end of the page Charging.
Now say cell #1 is at 4.0 volts and cell #2 is at 2.4 volts.
Now your charging without ballancer and you are pumping in the juice the same to both cells, the charger is looking for peak which is around 8.40 volts, ballanced that would be 4.2 volts per cell.
But where your doing just a regular charge cell #1 is at 5.0 and cell #2 would be at 3.4.
Good chance of cell #1 dieing because of over charge, also good chance of cell #1 bursting into flames because of being over it capisity.

Read up on these lipo's and follow the instructions and lipo's are safe.
Not learning to use lipo's rite can be dangerous.