I'll clarify. If the chip reader doesn't work 1 time or 100 times, my credit union has advised me (warned might be the better word) to NOT try and swipe it. More than one store clerk has told me "try it 3x then it will let you use the stripe". No, it won't in my case. My CU will decline the charge and lock the card. I simply use a different card and if it fails, it's their stupid card reader....This is true unless it fails 3x in a row it will let you use mag stripe as backup. Its usually worn out/damaged card, but occasionally its the reader.
If it doesn't accept the chip(insert) it wont even be flagged as a transaction so doing it 3x isnt 3 transactions its 3 failed card reads.
this then lets the system accept the mag stripe as backup transaction.