Before the age of famous people for example celebrities, clothes and fashion was inspired by hard working individuals that had creative minds and innovative thinking. They were the true designers who often worked long hours and late into the evening before they broke through the fashion industry. We know many famous fashion designers who started their fashion clothing brand from the back of the room with a sewing machine and few meters of cloths and these are the true so inspired fashion designers not some one that cant sing in front on thousands of people and cant even dress properly or appropriately for that matter.
We've seen many high profile celebrities starting a clothing fashion brand thinking that they will be successful but after a few months after the so called their own thinking of being creative stops then they can't bring in new ideas in to the market and that's why a lot of celebrities fashion brands disappears after a few months after their big launch parties.
How ever celebrities inspired clothing such as a plain t shirt with a famous picture of celebrity with printed on black and white ink and t shirt looks very classy and if that person was from the old and retro old school days then that black and white t shirt looks very good and that's why sales to do with retro and celebrities looks great and sells very good too.
When celebrities or even when famous people say a word especially a catchy phrase like "Yes We Can" these short words gets printed on t shirts like wild fire. Companies will tend to focus on latest events like elections, parties or seasonal events to think of slogans and images to print on the clothes and t shirts.
Why you may ask?
Well the simple question is because they will have an audience that they need to cater for like their fans and their fans look up to their fashion brand to bring them fresh new slogans so that they themselves can be up to date with local events. Also if it's a funny slogan then they want to buy the t shirt so that they are the person that people laugh with, which can make some people very popular indeed.
People want to wear funny slogans or images printed of their celebrity to show true devotion as some people think their celebrities to be their religion and god in some cases. Fashion clothes tend not to last very long compared to other clothes that you can find in non fashion clothes retail shop, this is because it's a trend that people buy one part of the fashion and then quickly buy another part of a different fashion. Ladies especially want to be known individually for wearing the very best and the very expensive so that they can show off to other people and this gives a high status of themselves, or at least that's what they think any way.
So now you know why celebrities start fashion brands and fail in some cases and why people would wear celebrity inspired fashion clothes.