Everybody judges "books" by their cover.
Presentation is the first impression someone gets about the site.
Front page is the cover, but every page is a landing page. Not everybody's first contact with your company website is on the index page (unless your site is very poorly optimized). People can find your inner pages, blog articles, services or product presentations, therefore all these will need to have a great design, an impeccable presentation and charm.
First impression will have to show the essence of your business. It will talk to the targeted audience saying "hey, this is what you need". It will give them confidence, trust, it will make them feel comfortable and interested.
The nice design of your website needs to be paired with a great structure. At this point is all about user acquisition and the user experience on the site.
The visitor has to find easily what he needs, to be suggested things of interest and convinced to act. Every moment of confusion is a step back from conversion. That's why you need to have a great structure where everything is easy to find, only a couple of clicks away, so that the users can sail smoothly on your site.
Structure is very important for user acquisition as well, something that many forget. There are structuring guidelines for search engine optimization as well. A well structured website will rank better in Google, bringing you organic visitors and conversion, which should be a goal for your business, because is the cheapest way to acquire new customers on the Internet.
Your brand is the soul of your business. It represents you in all areas and is a measure of your reputation.
A good domain name, a nice logo, a catchy slogan - what good are they if nobody knows them? Make them popular, recognizable. We live in the era of the social marketing where we can reach hundreds of millions of people with one post. But the competition is fierce in all domains - that's why you have to be if not the best, the most creative and likable on the market.