NPR has an article about the fashion world. Like in the software world, here things happen fast. Stuff that is new now, is uninteresting tomorrow. Like in the software world, a lot of copying and imitating is going on. But although the designs are trademarked, there are not a lot of lawsuits about who copied wat. Lawsuit take a lot of time, are expensive and you never know who will win. It is better to put you energy in coming up with new ideas, seems to be how the fashion people think.
Both the music and the software industry used to be like that. Copying was a form of flattery that didn't hurt the leaders. The leaders had moved on by the time the copycats had there knock-offs ready. Nowadays, we have patent-, trademark-, trade secret- and copyright laws to stop the copyers in their tracks.
It has been argued that strong Intellectual Property (IP) laws spur innovation, because new inventions are protected from copying and therefore there is a stronger incentive to come up with new inventions. You might just as well argue the other way around: if a company can exploit its IP without competition, because nobody can copy it, why would it innovate before all the possible money has been made from that IP? Keep it the way it was.
Of course there is a big difference between having competitors imitate your fashion item/software program/muscial style and having somebody making an exact copy of your song or computer program. But copyright law usually stops both. Microsoft has to charge something for their programs in order to pay their programmers, so allowing the general public to just copy everything would probaly mean that they would no longer develop MS Office (which would be fine, but that is not the point). But copyright law also grants Microsoft the right to exclude third parties from improving Excel or Windows and making money off that. Microsoft has a monopoly on that. Obviously, this means that less innovation is going on than is possible.
The question is, of course, whether a copyright law could be made that would allow software companies to charge for their products, while making it possible for other software companies to improve on the original product. Any suggestions?