Not always! How many of us have had an exchange like this:
You, to the guy behind the counter: "I only see one Anco 12-14 wiper refill on the shelf. Could you please check if you have any more?"
Counter guy sez "What year, make and model are you working on?"
You sez "It doesn't matter, I just gave you the part number. Anco 12-14. It's a 14-inch wiper refill like this what I am holding in my hand."
Counter: "I need a year, make and model."
You: "Fine, whatever. It's a 1972 Dodge Dart."
Counter: "Truck or car?"
You: "Dart. It's a car."
Counter: "What engine?"
You: "It doesn't make any difference! They all used the same wiper! Just pick one!"
Counter: "I need to know what engine. Does it have the one ninety eight three point two, the two twenty five three point seven, the three eighteen five point two or the three fifty five point seven?"
You: "There's no such a thing as a 350 in a Dart."
Counter: "Three fifty. Ummm...sorry, we don't have parts for that car."
You: "No, I said it couldn't have a 350 because they never came that way. A 350 is a Chevrolet engine, and this is a Dodge. It has a 225!"
Counter: "OK a 225...and does it have drum or disc brakes?"
You: "It has 14 inch wiper blades. Anco 12-14s. I can see them on the shelf behind you. Over your left shoulder. Can you please just grab me another one to match this what I have placed on the counter in front of you?"
Counter: "Uhhhh...I have to check with my manager...and he's on lunch...I could take down your, like, name and number...I guess...if you really want me to. That would require paper...and, like, a writing thing...we have these really kewl headlight blackouts, they look phat if you want to impress the chizzicks and, like, stuff. They're on aisle four."
You: "<unprintable>"
Counter: "Uhhhh...like...what-EVAH..."