OPT makes the first hire easy and the second year terrifying. The question is not OPT vs O-1 — it's what happens when OPT runs out.
You can hire a recent graduate on OPT with no petition at all — easier than anything on this site. The trap is the horizon: work authorization expires on a schedule, extensions are field-limited, and the traditional continuation — an H-1B — now means a window that opens approximately March 2027 and a lottery draw. Employers lose trained, productive people to pure calendar mechanics.
Six months before the expiry date, not six weeks. If you have an OPT employee you intend to keep, talk it through now — the case builds better with runway.