If that's illegal, then there are a lot of criminals walking free and raking in money.

Copycat startups are everywhere.

I am not a lawyer, and you should talk to a lawyer to get insight on your specific situation.

That being said, in my opinion it is fine to use an existing product/service as inspiration to create your own company. If you can do it better than competitors than congratulations! You will be successful!

The issues you are talking about are usually around similarities in patented tech, products, etc. For example, Apple has a lot of competitors, but there is a reason why none of them seem to build the same product with the same features at the same quality as Apple. They own a lot of the underlying tech. Hope that helps! Let me know if you want to go into more detail.

Not at all go for it. If you need a go-to-market strategy, call me, I would be willing to evaluate your idea and give you free advice to get started.

So long as you're not using any privileged information that was obtained in an illegal manner (i.e. as a former employer) and are not infringing on any of the competing company's intellectual property, there is nothing illegal about improving upon an existing idea.

There may be some nuances to your specific scenario depending on your location, the company etc., but in general, competing with an existing company using public information is absolutely fine. Open competition is a cornerstone of capitalism. In my experience, a large majority of innovative companies have been contemplated by others, but the truth is that turning that idea into a successful company is 10% idea, 90% execution.

If you would like to discuss the facts of your specific situation in more detail, feel free to set up a call.

This is in essence, the cheapest way to start a business. You have rightly not stated what the product or service offering is. So we can only offer general advice.

I work making businesses more effective, both in terms of IT and lean innovation practises. There is nothing to stop someone setting up a business and making the same thing or offering the same service as someone else, but faster and cheaper. It certainly isn't illegal as long as you don't violate a patent or other intellectual property in some way. The reality is you have to understand what IP exists (copyright, design-right, patent, registered trademarks...) and not every one of those applies to all services. Indeed, if a product or service is "obvious" to an expert in the industry, or it's public domain, patenting it can be considered indefensible anyway.

Most businesses who are second entrants off the back of a primary entrant who's idea is proving itself, have a much cheaper entry to the market and they can build on the lessons their first mover competitors have learned (or failed to learn). Doing what you describe can still be innovative. The classical example of the Toyota production system transformed the production of cars not just in Japan, but across the world. They couldn't patent the car, since that existed already and the production system they created could not defensibly be patented anyway. In any event, make sure your IP is protected once you do manage to do it.

If you'd like to discuss this further, feel free to book yourself a call. I'd be happy to help walk you through it.