Why do manufacturers persist in fitting glass jars for jam etc with a lid forced on so tightly that it is impossible to open the jar?

The normal procedure is as follows:

1. Grip the jar in one hand and try to twist the lid – failure.

2. Grab tea towel for extra grip and try again – failure

3. Hold metal lid under running water hot tap (Metal expands with heat) – failure

4. Boil water in saucepan and hold jar lid downwards in boiling water – partial success – lid now turns but you have burnt fingers and top of jam has melted into a liquid!

Drastic action called for so ordered up for delivery an implement that purported to enable you to remove the top of any size bottle or jar. Yes Michael Gove I know we are only supposed to order essential items but it is essential that gain entry into my jar of Tiptree Black Cherry jam. Yesterday the postie tip toed from the gate to the front door. He placed a small parcel against the door, knocked on the door and when I waved from the window to confirm that I had seen it sprinted at a speed Usain Bolt would have been proud of back out of the gate.

The parcel did contain the gadget which looked rather like a superior can opener and wonder of wonders it effortlessly enabled me to gain access to the aforementioned jam.

Of such small successes are we constrained to at the present time. This also leaves me to the major decision of today. For breakfast do I have two or three slices of toast with Black Cherry jam?