The last column is a little arbitrary. Burn and Learn and the Oscilloscope are the easiest to use, because the engineer is familiar with programming a device and using the oscilloscope. Simulation can be easy or more difficult depending upon the peripherals and signals being simulated, so it shows as medium complexity –your usage will dictate the complexity of the set up. The Logic Analyzer and ICE are listed as medium ease of use, although tracking all the address and data busses might require a great many clips and wires –still it is a common task done often by firmware engineers. The ICE is simpler to set up since all the trace lines are connected internally in the Probe and Pod. ICD requires observance of some design considerations for it to function, and it shares some resources on the application. Minor hardware and software trade-offs are necessary to use the ICD, but the ICD provides many of the functions of the more expensive ICE.