Uncovering a perpetrator may give insights into various security issues, such as infiltration methods, communication channels, etc., and may help in enacting specific countermeasures.
[1][2] Nissim Ben Saadon argues that the task of cyber attribution makes sense for major organizations: government agencies and major businesses in sensitive domains, such as healthcare and state infrastructures.
However most small and medium businesses (SMB) gain little in "postmortem" identification of perpetrators.
In BEn Saadon's opinion, it is unlikely that a particular SMB was specifically targeted; rather the incident was a crime of opportunity, exploiting a detected vulnerability, and with limited resources it is wiser to spend it on identifying the vulnerability in question and eliminating it.
[1] For governments and other major players dealing with cybercrime would require not only technical solutions, but legal and political ones as well, and for the latter ones cyber attribution is crucial.