Inbound is the opposite of outbound marketing. So, instead of cold calling and actively promoting yourself, inbound marketing's goal is to get new customers to enquire about your business or buy from you, which is inbound, through a long-term relationship that has been nurtured through content.

The keyword here is long-term because inbound marketing is not an instant fix to your sales number. It works on educating prospects, helping them solve their issues and improving their lives without selling anything. You do this through many ways including regular blogging, webinars, live sessions, newsletters, social media posts, etc. Once they trust you or your brand, they will be more open to buying your products and hiring or using your services. Once you've built a useful and effective user's funnel, then inbound marketing can give higher ROI than advertisements and other forms of marketing. 

James Artur Inbound marketing is a newer mindset of marketing that focuses on creating content people need, when they need it, rather than just pushing information at them. ... Strategically sharing your remarkable content in blogs, emails and social media helps attract the right visitors and convert them into leads.
It will help you reach new markets and audiences.