> **314.29 Boxes, Conduit Bodies, and Handhole Enclosures to Be Accessible.** Boxes, conduit bodies, and handhole enclosures shall be installed so that the wiring contained in them can be rendered accessible without removing any part of the building or structure.

The rationale for the rule is very simple. At some point, someone will need to service or inspect this wiring.  The electrician *cannot possibly be expected* to remove every single screw-down panel in the entire building *on the blind hope* that a junction box or pull point *might be* behind it. 

(only to find out the mystery box or conduit body is actually behind none of them, and is actually behind finished drywall). 

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Separately, you are relying on a **false** premise that the plywood panel can be removed *non-destructively*.  That doesn't work out IME. The screws seize up (excessive torque to remove, camming out screw), or they expand from moisture, or they stick, or one thing or another.