Tetra mesh quality before and after prism layer
 

Hi,

Till now I have only used structured hexa meshing in ICEM for my geometry and I am new to tetra meshing.
I have followed the method for tetra meshing in ICEM tutorials to create a tetra mesh for my geometry. Before creating prism layer on the required walls of my geometry, I go through mesh diagnostics, mesh quality check and mesh smoothing to get a mesh of quality ~0.39.
This level of quality for the tetra mesh seems ok if I compare with quality of some of the tetra meshes stated in ICEM tutorials.
Next, I go ahead and create prism layers.
The prism layers are created without any issue. However, if I check my mesh quality now, it drops down to <0.1 and is of the order ~ 5e-2. If I try smoothing (with or without keeping the prism layer frozen), the mesh quality does not improve.
Is it that the mesh quality parameter pertains to mesh without prism layers only? Or is my mesh really bad after creation of prism layers and I should try to improve it and check mesh quality everytime after creation of prism layers?

Thanks a lot for your inputs!