Three different problems with one name
People say a paddle is dead to mean three unrelated things, and the distinction matters because two of them end the paddle and one of them does not.
A dead core means the honeycomb inside has crushed or separated from the face. The paddle goes quiet and muted, the ball comes off slower, and the sweet spot shrinks. This is terminal.
Delamination means the face has separated from the core, usually near the perimeter on a thermoformed paddle. Confusingly, this can make a paddle temporarily hotter rather than deader, a trampoline effect that feels like free power and is also a failure. It is terminal, and it is the reason delaminated paddles get banned from sanctioned play.
A worn face is not dead at all. The texture has smoothed and the paddle generates less spin. It still plays; it plays like a control paddle now. That is a change in character, not a fault.
The tap test, which takes thirty seconds
Hold the paddle loosely by the handle and tap around the face and perimeter with a knuckle or a ball, listening rather than looking. A sound paddle gives a consistent tone across the face, with a predictable change at the edges.
Listen for a dull, flat thud in one region where the rest of the paddle rings. That is a localised core failure, most often near the top where most mishits land.
On a thermoformed paddle, work slowly around the perimeter. A change in pitch between one section of edge and another is the signature of internal separation, and it is the most common failure on the current generation of paddles.
Then press firmly on the face with your thumb in a few places. Any softness, give or crunch underneath is core crush, and no amount of cosmetic condition compensates for it.
The sound test, and what it will not tell you
Play a few balls and listen. A healthy paddle has a crisp, consistent pop. A failing one sounds dull or, on a delaminated paddle, unusually loud and hollow.
The trap is that a delaminated paddle can feel better for a while. Extra power with no apparent cause is a symptom, not an upgrade, and players regularly mistake it for a paddle breaking in. Paddles do not break in.
What none of this tells you is how much face texture is left. That is a separate check and a tactile one: run a thumb across the face and feel whether it catches. On a raw carbon paddle that grip is most of what you paid for.
What is worth fixing
The grip, always. It is the cheapest component on the paddle and the one that most changes how it feels to hold.
The edge guard, sometimes. A lifting guard can be readhered and a missing one can be replaced, though on an older paddle the cost rarely justifies it.
The core and the face, never. There is no repair for a crushed core or a delaminated face, and there is no resurfacing a face that has lost its texture. Anyone offering to is selling you something else. This is why paddles that fail these checks are declined here rather than graded down and listed cheaply.