During a promotional offer, I bought a pair of reading glasses but found them unsuitable as my eyes were watering. I bought a second one and it was fine. Upon checking the readings, it was discovered there was a significant difference.
Please note the eye testing was carried out by different persons. When this was pointed to the store, they refused to renew the defective lenses, stating various reasons. Most of the staff are not very knowledgeable on the procedure for testing eyes.