Spotting abnormal tire wear and correcting the cause can significantly extend tire life. Normally, tires will wear evenly across their surface until they reach the wear bars, which are 2/32nds of an inch above the bottom of the tread. When the tires are worn to the wear bars, they should be replaced.
One shot (1.5 ounces) of espresso has about two tablespoons of coffee (about 1/4 ounces). For best flavor, one shot of espresso, or two tablespoons of coffee, should be used to make 6 ounce of coffee drink. Likewise, a 12 ounce coffee drink will taste best with two shots of espresso.
In my opinion is quite simple: at the end of the day, you'd have used much more coffee. With one kilogram of coffee beans, you should be able to make about 140 shots if you'd use 7 grams, only 100 if you use 10 grams, and in this case the cost per shot you'll pay would be almost 50% more!