Why are uggs so popular?

In the 1960s, ugg boots became a popular option for competitive surfers,[6] who used the boots to keep their feet warm after exiting from the surf.[7] It was surfing which helped popularise the boots outside of Australia and New Zealand, when surfer Brian Smith started selling the boots in the United States through the company Ugg Holdings, Inc. in 1979.[7] Later, ugg boots emerged as a fashion trend in the United States, with celebrities such as Kate Hudson, Sarah Jessica Parker and Pamela Anderson wearing the boots, increasing demand.