Add your YES/NO illustrations here. Hopefully some noobs will stumble across this (or some not-so-noobs) and find a better path to enlightenment.
PROPER BASE SKETCH PROTOCOL:
PROPER BASE FEATURE PROTOCOL:
Do not start a part without symmetry unless you have a good reason!!
The symmetric part will have planes in the center of the part and will often make mating much easier.
It's a sign of inexperience to not leverage symmetry, especially when it is so easy in so many cases.
Plus, would you start a cylinder like this??:
That's essentially what you're doing if you sketch a base rectangle at the corner.