I have run a 12/2 rx from a unfinished basement and poked a hole thru the floor and installed a 20amp female cord connector with a cord from the dishwasher with a male cord cap. I am being told that the RX should be run thru the cabinet to reduce the risk of the dishwasher being pulled out and will damage the wire. In all my years this is a new on me. The job is in Ma. Any opinions out there.
Thanks Mike

Are you saying you put a 'cord cap' on the NMC? Then a cord to the DW?

As to the routing of the NMC, it has to be protected from physical damage. Possible or probable, that's an AHJ call.

Most DW here are hard wired. The cord (plug-in) ones the receptacle is accessable, under the sink cabinet.

As far as the cord cap on the NM. Is it rated for NM?
Either way,I would install a rec.
It does not Have to be cord/plug connected.
BUT,If it is, There are rules.

Regard to location: 422.16(B)(2)(4):
Shall be in the space occupied by the appliance or adjacent to.
(5) must be accessible.
(NEC-2008)

I have several issues with the installation.

The NM ought to have terminated in a box,with a receptacle. There are a few reasons for this.

The first is that, by putting a cord cap on the NM, you're treating the NM as if it were nothing but an extension cord. We are not allowed to use such cords as a substitute for permanent wiring. Where we do use a cord, we are not allowed to have that cord pass through a wall or floor - even passing the cord through a hole in the cabinet to the area under the sink is kind of 'iffy.' (I know, it's often done ... but let's not get into debating the exact meaning of 'wall.')

Putting a cord cap on NM is a bad idea. The grip on the cord cap is essential for providing strain relief, and the connection will not pass the required tests. I can say this, as I have tried it, under lab conditions. The cable will work loose over time.

The idea of adding a cord and plug has been the matter of lively debate. at both other forums and at listing agencies. Personally, I think the debate is silly, and the listing agency folks have another concern that never comes up: that is, if you add a cord, in their eyes that makes it a 'portable' appliance, and their standards MIGHT differ a bit. There is also some concern whether the appliance is equipped to provide the cord with proper strain relief. For the most part, it's something I wouldn't lose any sleep over. In my view, the ability to easily and definitely disconnect the machine makes up for a lot of lesser sins.

Receptacles in the floor behind a dishwasher don't seem like such a great idea. What about putting in a box and coming off that box with an armored pigtail (BX or liquidtight) to the female connector? NM shouldn't be used as an extension cord, it's not designed for that.

It makes little difference to damage whether the cord is passing through the floor or cabinet. It merely has to be in an area free from interference with the dishwasher, and that envelope can change from unit to unit.

This is just my opinion and I'm not posting this as a flame attack or anything of the sort, but this just sounds plain rough, I would never even contemplate doing a job that I am expecting people to pay money for, in a manner like that.

Mike:
I have to agree with what you said above 100%

Steve:
I origanally thought to include "RED STICKER" in my orig. reply above. As to running the cord thru the floor;400.8 (2)prohibits that. As Leland said, adjacent to or within the occupied space; and accessable. Problem solved with a single receptacle inside the sink cabinet, at the back.

And, once again Reno eloquently stated the pros and cons.