Booster pack replaces a suspect or low battery to give you enough oomph to try starting.
If you have a bad earth then that is what forms a poor circuit either causing high resistance and low power or a complete dead circuit.
A booster may help starting but he bad earth will remain and the problem recur and your battery on its own not be able to crank the engine enough.
Bad contacts/poor earth is a common electrical gremlin.
Long term, clean your battery terminals, earth points, protect with petroleum jelly.
Make sure securing bolts and earth cables are in good nick, clean everything or replace with new.
I used stainless bolts when changing my earth straps, petroleum jelly as well.
I HATE a non- starter and have always kept the ignition, battery,starter circuits in good nick. These are the more common causes of non-start.
Any problems were then usually fuel related.
That was for older cars without a multitude of sensors!!!
