Rubber pads should be avoided for vibration isolation because they can cause resonance between machines and foundations. Resonance leads to amplified vibrations instead of isolation, increased fatigue and breakdowns. Over time, rubber pads compress more which worsens the resonance issue. They also need frequent replacements that increase long-term costs compared to base isolators, which provide over 95% isolation and last lifelong with much lower dynamic loading and costs over 10 years.