Consistency

Consistency
"A harmonious uniformity or agreement among things or parts." Designer is to create order, to make
it easy for users to find the information they are looking for.

Example 1
In the below picture same coca cola logo used all products. 

Coco cola logo follows consistency

Example 2

Nike logo follows consistency

Example 3

In apple product designers consistency follows not only logo they also follow consistency operation of same products.

Apple logo follows consistency to all products

Example 4

Consistency umpire signals in cricket.

Consistency umpire signals in cricket

Example 5

Consistency in police uniform.

Consistency police uniform

Advantages of consistency

1. Consistency eliminates confusion and users easy to identify the product. 

2.  Consistency save the company money and time.