Hi,
As per my knowledge, this is the SAP ERP standard behaviour to create Inspection lots when the Inspection Types are assigned to Material and Inspection plan (or Routing) or Material specification is also assigned to that Material (Prerequisites).
MICs are added to records the results only. Adding or removing of MICs do not affect Insp lot creation. These are the Inspection Types and Inspection plans who play the key roles in lots creation.
If you don't want to create Inspection lots for that particular Material just remove the Inspection plan or material specification.
See the process flow of Inspection lot creation.
Inspection Lot Creation - Inspection Lot Creation (QM-IM-IL) - SAP Library
Inspection Lot - Inspection Lot Creation (QM-IM-IL) - SAP Library
Regards;
S Ahmed