Because you can't spell decanter without CAN. Nor can't, actually. But we're gonna just focus on the positive here.
All my life, people have been telling me the things that I can't do. "Michael, you can't go outside and play because it's raining." "You can't play professional basketball because you're only 5-feet tall." "You can't just run into a parked car on the road and then drive off without leaving a note."
Well, I got sick of people telling me what I can't do. So the word "can't" is no longer part of my vocabulary. Now when someone says to me, "Michael, you can't let your wine out to breathe!" I say, "Yes I deCANter!"
When someone walks up and proclaims, "That deep punt can't increase the surface area to entice the rich flavors and aromas out of the wine!" I say, "Yes it deCANter!"
And the next time someone tells me that I can't improve my experience with a bold red wine by aerating it in a hand-blown, lead-free crystalline quartz vessel with an elegant and sleek design, I'll turn to them and whisper softly in their ear, "Yes. I. de.CAN.ter."
I might even follow that up with an adamant "You're not the boss of me!" and a big, wet raspberry. We'll see. I'll just play it by ear.