Car having trouble starting without battery boost. Brand new battery. on 2000 Volkswagen Jetta

So I went to start my car and it wouldnt start. I have lights and gauges, but when it comes to starting, its a no go. But when I hook up jumper cables or a portable battery charger it starts right up with no problem or issue. The battery is literally 2 days old and had been changed out just in case of a defective battery. So I went thru two new batteries and was told by my neighbor it wasnt the starter or alternator. So what?????

Asked by for the 2000 Volkswagen Jetta
2 answers 3 comments
What kind of battey, what brand just for the hell of it??
Check for loose connections on starter and grounds..
Its an everstart maxx H5. Second battery I got within 2 weeks. Car worked fine for a week and a half.
perform a parasitic drain test. There might be a system still getting power when the car is turn off.
Even when I turn the car off, I can still hear humming within the block area
YeAh thats a cooling motor circulating the coolant , that s normal, it could be that battery again ,
See if part store will do a battery load test or
Were you bought it...