In formalized program inspections, the code is distributed among the reviewers. These reviewers inspect the code and then review meeting will be conducted to discuss the findings of the inspection. It takes lot of time to complete the review. In general, while planning the project, the time needed for the project completion will be estimated which includes inspections and reviews.
The Agile methodology is an iterative method in which continuous iteration of development and testing is done throughout the software development life cycle. The code is continuously changed in the project. It does not make sense to stop development and take some time for formalized program inspections as the code changes continuously. Thus, the formalized inspections do not suit for a software that is developed using agile methods.