This here, is a door. Good solid construction, bolts, keeps you safe! Keeps out the elements if we had many of them, unwanted visitors...
This door is a structural foundation that allows entrance in and out of your masterwork! But it's not just some straight line then the fun swingy one you make with the stencil.
It's more than that! It's a symbolism! It's a barrier between you and everything else!
Now you can see it as a protection or a BARRIER! That door could hold any old thing on the other side! It could hold a high bidder, it could be a disgruntled client, it could be a wagon just FULL of explosive chemical compounds that got sent to you accidentally.