It has been narrated that Imam always tolerated criticism with open arms and he advised relevant authorities to undertake serious efforts even if they face difficulties on the way to serving public masses.
Dr. Mohammad Hosseini Beheshti, an Iranian jurist, philosopher, cleric and politician who was right hand of Imam used to advise his colleagues and people that he would welcome any criticism regarding his speech and governmental programs.
Dr. Beheshti used to say donot just hail and praise him but freely exercise your right of constructive criticism.
Extracted from a collection of memoirs about Imam