They look similar in photos. They don't perform the same way on your floor.
Most garage floor "paint" sold at hardware stores is a thin acrylic or latex coating that sits on top of the concrete surface without truly bonding to it.
Because it doesn't penetrate or bond the way a professional coating system does, floor paint tends to peel, chip, and wear through in high-traffic areas — often within a year or two, especially under vehicle tires.
A polyurea or polyaspartic coating system starts with mechanical surface preparation (diamond grinding) to open the concrete's pores, allowing the material to bond into the surface rather than just sit on top of it. That bond is a major reason coatings last dramatically longer than paint.
Paint is cheaper and can be a reasonable option for very low-traffic areas or a short-term fix. For a garage that sees daily vehicle traffic, a professionally installed coating system is a longer-term investment that avoids repeating the job every couple of years.