The LC (Labor Certification) process that's being described is a requirement to sponsor an employment-based immigrant visa; what most people call a Green Card. It is not, generally, a requirement for non-immigrant visas like the H-1B.

For most people coming from abroad, they're either being hired initially on an H-1B and then - usually after their time on that visa is up - their employer might sponsor them for the immigrant visa.

Others come via the intracompany transferee visa, the L-1. In certain categories, e.g. L-1A, for executives/managers, that visa allows an application for an immigrant visa without the LC process.