Clamp Overlap takes the smallest Edge and tries to bevel that, but as soon as two Vertices meet, it stops. As your Object is 3.25cm high, it cannot bevel 10cm, in fact there are many much smaller Edges in your model (and it would only need one).
Here the smallest Edge is 20cm, so there is no clamping with a 10cm Bevel:

But When I Bevel one corner Vertex, Clamp Overlap kicks in:

Of course that part will ‘explode when turning off Clamp Overlap:
