PVRTexTool Compressed Texture Quality


I was using PVRTexTool to generate compressed texture from a .tga file. Post generation, i felt there was a significant degradation in quality once texture is compressed.

Following are my stats related to file:
Component : RGBA
Format : PVRTCII 4bpp

How can better quality be achieved if existing quality is not matching the expectation.

P.S : Sorry, cant post the output for comparision