With so many online transactions and important business communications happening on the internet, there is a very strong reason why you need to get an SSL certificate installed for your website. There are numbers of online threats, virus, malware, hackers who want to hack into your account or steal your data.
With SSL Encryption you can protect data transmissions (i.e. browser to the server, server to server, application to the server, etc.) You can authenticate the server you are connected to is actually the correct server. Ensure data integrity that what is requested for and what is received is the same. Search Engines like Google also give more importance to secured websites and rank them better than less secured websites.