SSL certificate is not important… the security of a website depends on
- how it was programmed.
- the skill of the person hacking your website
- if anyone with admin access has been compromised.
- how secure the admin’s password is.
If a site owner wants to make other people with the same attitude as @techscorpion and @Ndianabasi feel safe using the site then SSL can be used but it does not determine how secure a website is.