How would a customer indicate wanting half the syrup amount?

When a customer wants half the syrup amount, they can use the "-" symbol to convey a desire for a reduction in the standard quantity of syrup typically included in the beverage. This shorthand effectively communicates that the customer wants less syrup than is usually added, allowing for a clear and concise modification to their order without ambiguity.

Choosing to indicate "no syrup" would completely eliminate the syrup rather than reducing it, while using the "+" symbol could mistakenly suggest that they want more syrup instead of less. Specifying the amount can certainly communicate the desired modification, but it is less efficient than using the "-" symbol, which is a direct indication of wanting a reduced quantity. Thus, utilizing the "-" symbol is the most straightforward method for expressing the need for half the syrup amount.