So just to speak in general terms, and not implying anything about Basschat's security:
When you sign up to a new site/service, you don't know whether it's got sensible security precautions to guard against password guessing (e.g. lockout/timeout after a small number of failed attempts).
And you also don't know whether your password will be stored securely, i.e. not likely to be leaked and also not easily cracked if it does leak (by being properly encrypted etc.)
So as a general rule of thumb, why not do everything you can to protect yourself?
- Use a strong password; long and complex is best, but otherwise long and simple generally beats short and complex (see table below)
- Use a unique password, so in the event of compromise you'll only have a problem with one site
- Use multi-factor authentication, if available
Illustrative guide to how it long it takes to crack a leaked password:
Terms and conditions apply; your mileage may vary; source: https://www.hivesystems.io/blog/are-your-passwords-in-the-green