Ammi Jaan kahti thi Railfanning se bada koi dharm nhi hota or koi Railfan chhota nhi hota - Shanzil Kabir

For several reasons.
1) Traditional ICF coaches are NOT unsafe. They are anti-telescopic. They have crumple zones at either end of the coach near the bathrooms, which absorb the energy from head-on impacts and reduce damage to the passenger areas. The reason these derailments have caused several deaths is because of the screw couplings used to connect the coaches. If LHB coaches are run with such couplings, they will also result in substantial deaths ( definitely less than ICF coaches, but still the core problem is the coupling more than the coach). Thus from the management's perspective, they preferred running with ICF coaches, hoping track maintenance would take care of accident reduction ( which obviously did not work out as planned).
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Running with LHB rakes has several hassles, like EOG maintenance, re-fuelling, connecting rakes is a more tedious task as there are extensive electrical connections. ICF coaches are self-generating, which allow a lot of flexibility in operations.
3) Manufacture and maintenance of LHB coaches is also more intensive.
All these factors, and the lack of HOG locos meant that the management was not very keen on stopping ICF coach production. Even now, the shift to LHB is more because of the press coverage for the recent derailments and public scrutiny. Given a choice, they would probably prefer using CBC ICF rakes until the HOG systems or self-generating LHB coaches are ready.