Q1:Is this a coincidence? Prior to my trip to the shop four days ago, I never had any indication that my battery was failing. I had snow tires, rims installed by the local tire store. During the installation they opened the hood and did a 22 point inspection.. unsolicited by me. When the car came off the lift, it would not start. Hmm... the technician said that he did NOT leave the key turned on in the ignition. He also tried to jump start the car... First time that he did that, he connected directly to the battery. It did not turn over. He tried again and got a second battery booster pack and this time at my insistence they jumped it using the correct terminals in the engine bay. He ran a diagnostic that shows that one cell was bad and readout at 10.2 volts. The battery is OEM, and the 2003 530i has 55,000 miles. Nonetheless, the battery never had shown any sign of failure, slow turns, etc. Q2:Could they have inadvertently discharged it somehow during the lift and/or the inspection? Now the battery needs to be replaced. They were very apologetic and did not charge for the tire switchout or try to upsell me. But I am stuck with a nearly dead battery (barely will turn over) and want to know if they are at fault. Q3: Any reason to buy OEM vs. say Optima vs. Die Hard. Q4: Could they have done additional damage to the computer when they did the first jump start. (When I drove home fuel gauge read empty (I had half a tank)... and the temp gauge said minus 40F. Please advise.