Spam. No one likes it. No one wants it. No one needs it. However, it is there and is likely to be there for the foreseeable future.
All we can do as responsible mail server administrators is to ensure we are not part of the problem by not running an open relay and locking down our services as much as possible.
One tool that can help our legitimate email not being classed as spam is to set a Sender Policy Framework (SPF) record in our domain's DNS zone.