Air India and flight delays

My Mum had displeasure flying Air India, LAX to Delhi because of the long flight delays in reaching the destination right from the take off in LAX, intermittent stop over in Frankfurt. The flight delay made her miss her connecting flight Air Sahara, Delhi to Chennai and to the sad of it, she was made to wait till the evening for the next connecting flight from sahara. Why does Air India leaves passengers stranded in the airport so often? Inefficiency of the flight crews? Operational glitches? mechanical difficulties? Air India – The National Carrier has gone down the drain in making its passengers suffer with its long flight delays and  keeping its passengers uninformed. Now am cursing myself why the heck I chose Air India for her travel this time.