inherent operating constraints of constituents vendors provide minimum measurement functionality (snmp, netflow) no incentive to do more since it is expensive and does not sell boxes providers dis-incented to share data with others due to competitive and privacy concerns no apparent payoff (beyond what they do already) software engineering (operating systems, applications, routers) lack Internet systems perspective renders Internet vulnerable or non-optimal measurers/researchers oblivious to real world of costs, e.g. opex/capex ratios largley unable to target measurements at immediate provider problems struggle with interpretation of non-standard data sets users as if we could forget if policy makers ever had a role to play anywhere.. (manipulator of market forces to protect/enhance consumer welfare)