The most noticeable detail in a blazer are its buttons. The kind of blazer buttons depends on the purpose of the wearer. Clothing is a part of how a person communicates and sends a portion of message and personality to people who are around to see.
Mainly for decorative reasons, blazer buttons can be found in different parts of the shirt. The cuffs, say for example, have varying number of buttons that usually has no real purpose except for decoration. Blazer buttons are where customization typically happens. So it is important to remember that buttons may be the part that can be difficult to replace. Once you lose one button, you will most likely have to replace all buttons just to restore the style of your shirt or any apparel. A small inconsistency even with the small detail of a button makes the whole blazer shabby.
Designers have to be very careful in choosing blazer buttons in accordance to the jacket style, fabric, color, and even the threads. The material of the buttons also plays a big role to make a blazer appear very authentic. Faking a blazer defeats the main purpose of a blazer, and that is to look fashionable under a cold weather. Otherwise, a common jacket should work just fine, fashion aside.