Would you run a marathon without any training? Just because someone offers you a bib to join the race, it’s probably ill-advised line up for the start without building up your endurance.
In the end, even if you are able to limp across the finish line, it’s highly unlikely that you would place among the elite runners who approach the race with discipline, strategy and a plan to win.
Law school is no different than a marathon, except that it is significantly more competitive (and expensive) and only a select few at the top of the class cross the finish line realizing a meaningful return on their investment. Walking into such an environment without preparation, but expecting success, is an incredibly risky move.