If you think that you would be just fine squatting at home by yourself without the proper gear or people to spot you, we might suggest that you research squatting fails on the internet. There are plenty of tales of athletes that felt they were above needing help, and it is a difficult thing to watch their knees begin to buckle, and the barbell soon falling on top of them. It is probably in your best interest that you never test this theory out yourself- especially when dealing with heavier weights. There is no way that you can get stronger if you hurt your back on a failed lift that was completely avoidable if you only had a spotter or the use of a cage.