Non-central polynomial potentials in two dimensions are considered.
Their unbounded decrease causing an accelerated escape of classical particles in some directions is admitted.
We show that quantization prevents such an "explosion" below a certain critical strength of repulsion.
An analogy with the well known fall of particles in a "too attractive" singularity is emphasized.
J. Phys. A: Math. Gen. 31 (1998) 3349 - 3355.