Same thing applies in creating new category of trains every time. Rajdhani, Shatabdi, SF, M/E, passenger were enough would have been better but now in addition to them we have Duronto, VB, AB, Jan Shatabdi, Garib Rath, Humsafar and what not. 🤦
In case of 3E the decision to price them near to 3A was the bad decision. They should have priced them atleast 25% less than 3A. This would have made a lot of SL class passengers willingly make upgrade to AC travel.