What are some examples of individual ministerial responsibility being strengthened?

When Home Secretary Priti Patel was quizzed on the lack of visas available for Ukranians fleeing Ukraine Feb 2023, education secretary in 2003 Estelle Morris resigned after a series of controversy about A level standards, Jackie Smith, Home Secretary during the brown government resigned after her husband claimed pornographic material on her expenses, Matt Hancock had to resign after failing to adhere to governments social distancing rules