In retail you have customer feedback and body language to guide the sales process. Online, the person can be from another country, culture and have comprehension issues. There is no physical interaction.
The sales process is very impersonal but the customer wants the same warmth and trust before buying.
Marketing is completely different. You have to sell from the start whereas a shop has time to build rapport or get a return visit due to locality. Your internet locality is the same as everyone else’s.
Attention span is MUCH shorter online, so the USP needs to be conveyed faster and with less words/pictures.
The process of buying is different from the norm and not all web users are comfortable and confident in the process, so it needs to be reassuring, familiar and easy.
Building trust and authority will take a lot of time and effort before you are the trusted supplier. Establishing reputation and a no-quibble return policy is important.
Just putting up a site does not equal sales or traffic. It takes a lot of effort.
Customer loyalty is non existent and they do not readily engage with brands online or on social media. 3% is a good conversion rate on social media, 10% on email. You need to prove value and worth to each customer before selling to them.