First of all, rubber band is an thermodynamic object which does not contain any potential energy if loose, this it's to be declared as "cold" if loose.
If you stretch a rubber band, it warms up indeed and then, contains potential energy which is needed to get back in old state.
Also, warm rubber bands are more elastic than cold ones.
Like shown here.
Due rubber bands wear of when getting overstretched, you should make them as elastic as possible before stretching and thus warm them up.
Do not wrap them at your wrist if they're cold, better put them into your pocket or hold them in your hands for a moment.
If they're warmed up, your wrist is a perfect storage due it keeps them warm.
Make sure the rubber band is warm, before you wrap them around your hair.
Do not store them at cold temperatures.
And of course, higher quality is more durable.
There's a german proverb:
"Wer billig kauft, kauft zweimal, wer sparen will gibt Geld aus."
If you buy cheap, you'll buy again. If you want to save money, pay more.