Harda Incident has nothing to do with this Loco Issue.
I have cited the Instance of Harda Incident for showing the maintenance standard of Railways. However, from the accident pictures a layman can guess what will be the toll of casualty whatever may be the figure furnished by Railways.
So " No loco is given a go ahead to haul a train unless it satisfactorily clears all the tests" this statement is also not beyond doubt.(Loco Performance figure of E-Loco is a TESTIMONY of recurring failures of Tap Changer Locos)
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kindly take a look at News Entry# 236830 I think you will understand the maintenance standard of Railways.

Hey, I don't mean to say that these locos should be used forever. I'm just saying that it's very impractical to scrap so many useful locos in a short time without the replacements getting ready.
Out of 190+ WAM4's currently operational, more than 170+ are being used for regular operations. Currently CLW's production is only at ~40 P7's per year with P4 production slowing down to ~20 per year. Add to this, the time required for testing and commissioning each loco, it'll easily take around 3 years to create good replacements for the existing fleet.
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CLW had produced exactly 500 WAM4s starting from 1970 and more than 300 of them have already been condemned as of now. As such IR has been phasing them out regularly and even now, IR is going ahead with a good schedule with most of the fleet scheduled to retire in phases in the next 3-5 years. (All of IRs elocos were designed for an expected lifetime of 40 years). Besides, they are capable of handing 24 coaches with ease, have less frequency of failures and are very rugged and simple to maintain (The MAIN reason for their longevity ). They can be used for a few years until we have enough P7s to take over from these legends.