Let me try
,, it takes 4 parts to make a door frame,,,two Stiles, and two Rails that have been milled the same...many cut all the parts at the same width at one time and then run them by the router bit, that the hard way and not the safe way.
If you use wide stock it's alot safer, you have more stock to hold on to and to go by the bit.
Then once the router bit has done the job on the ends and the sides of the stock they can be ripped them on the table saw safe and if you have any with rip outs they can be cut off clean and easy ..and the best thing of all the stock will match up because you used one board to make them all..
One more note,,,many get hung up on how to to cut the parts for the door and panel,,,if you use the magic number of 4 ,it's easy to cut your stock just right every time..you don't need your math books to do this..
Most R & P sets cut 7/16" or 1/2" deep,,,so in that way you rip all your parts to 2 7/16" to 2 1/2" wide, so to say if your door is going to be 12" x 18" ,,the rails will be cut to 8" long and the stiles will be 18" long.. 12" -4" =8" ..don't forget about the offset on the frame, 1/2" on all sides of the door frame the norm.
The panel is done the same way..magic number of 4