Why are some employers allowed to not issue 1099-NECs?

[darkpwca]

I have always been told, and see multiple references stating that employers/business must issues a 1099-NEC to their independent contractors / freelancers if they paid that person $600 or more during the year. I work for multiple companies who, whenever I've asked about receiving a 1099 (because I made $600+), have their accountants respond stating that it's my job to report my wages myself and they their company does not issue 1099s. Where is the line here? How come some companies don't have to issue them?

[KrisD15]

They do (have to), they just choose not to. 

If the IRS checked, they could be penalized. 

According to the IRS:

"If you pay independent contractors, you may have to file Form 1099-NEC, Nonemployee Compensation, to report payments for services performed for your trade or business. If the following four conditions are met, you must generally report a payment as nonemployee compensation.

You made the payment to someone who is not your employee;
You made the payment for services in the course of your trade or business (including government agencies and nonprofit organizations);
You made the payment to an individual, partnership, estate, or in some cases, a corporation; and
You made payments to the payee of at least $600 during the year."