An TLS/SSL certificate lends the stamp of authenticity to your websites. The HTTPS padlock lets your visitors know that your website is secure and all information that they may share with it is private and encrypted.
This is especially vital when your website handles confidential user information like logins and passwords, financial details, personal data, etc. Aside from the security aspect, having an TLS/SSL certificate also helps in SEO and makes your website rank higher in searches, as they’re perceived to be more secure than HTTP websites.