Instrumentation these days should not be installed just for the sake of ‘fashion’. Instrumenting the ground or a structure is important to derive useful and also critical information as follows:
Instruments are used to characterize site and ground conditions and soil parameters/properties e.g. pore water pressure, effective stress.
Instruments are used to verify design assumptions and to check that performance is as predicted so necessary measures can be taken if the parameters are unexpected.
Instruments are used to monitor the effects of construction on the structure itself or the effect of construction to existing nearby structures, e.g. crack, tilt & settlement.
Instrumentation can be used both to enforce the quality of workmanship on a project and to document that work was done to specifications.
Instruments can provide early warning of impending failures, allowing time for safe evacuation of the area and time to implement remedial action.
Instrument data can provide evidence for a legal defense of designers and contractors for legal claims of non-performance, damages or negligence.
Instruments are used to monitor the in-service performance of a structure while it is occupied without disturbing the occupants.