Music photography has to be one of the worst paid gigs out there for a free-chancer, but it seems to be the game with the most free-chancers in it.
There seems to be a few ways to 'make it' and that can either be on the back of a band you are working with who break and they take you with them then your images become in demand.
Or
If you are lucky enough to snap something that gets noticed by the agencies and or music press, someone there likes your style, thats when you start to get access and once you start to get access you start to get the shots no one else does and your stuff gets published and your reputation builds to the point bands want you to photograph them.
Or the good old you know someone who knows someone, so working with venues / promoters can get you contacts and access
At the moment there are soooo many people who think music photography is 'glamorous' and want to do it they go to every gig for about a year to 18 months then realise there is no money in it and get fed up with working for nothing, eating in kebab shops at 1:30 in the morning, having your work constantly ripped off on social media and used without credit that they give up and go and do something else.
Me personally I work a couple of small venues snapping up and coming bands working on the principle that one day some of those bands are going to be massive and if you have the images from the very early days they are the ones people will want. Imagine you had some early Sex Pistols or Clash photos in your collection that no one had seen for 30 odd years.
All the time I'm building a body of work that hopefully will contain enough quality to move me to the next level, and lets face it.. you cant practice this stuff at home... and I get into most gigs for free, I've had numerous albums gifted to me from bands, been published a few times so its not all bad.