Why is medical / insurance billing so complicated?

Not talking about a multi-week hospital visit, just easy stuff.

Back in April, one of the kids wasn't feeling well, so we did a virtual dr visit. The doc said to go to one of their clinics (it's a huge New Orleans area medical group that has four initials) and get a urine test. So we go, sample collected, I try to pay them, they say, we will send you a bill.

Yesterday, 5 months later, I get a bill which shows the amount I am owed after insurance. It's less than $30. I understand they have to bill the insurance company, who has to process the claim, and send it back, and then they have to bill us for the difference. But 5 months? For a urine test?

This morning I go online to pay the bill, put in my account info, and am shown an amount due that is exactly $25 more than what was on the bill I got yesterday. No other information about the balance is provided. So I call. Turns out, my other kid went to an after hours clinic last SEPTEMBER, a year ago, and a co-pay wasn't collected at the time. They sent out the bill for that on Thursday last week, so it was on their system, but I guess it hasn't arrived yet in the mail. That can't entail much more than a typical office visit.

I did check my bank records to see if I paid them anything around last September, and I did not, so it's probably a legit bill.

Our system is insanely, absuredly complex and full of bureaucratic BS. The amount of money that must be wasted every year has to be mind-blowing. Plus, the cash flow issues for the medical group.

I'm sure a government system would somehow be far worse, so that's not the answer. But for basic medical care, no hospital stay, just tests and urgent care visits, there has to be a better way, right?