The summary.
PER-ACCOUNT LIMITS ARE WHAT MAKE SHARED HOSTING WORK
Without them one site under load makes every site slow, and customers experience unexplained intermittent slowness they attribute to you.
Monitor per account, not merely per server — totals tell you something is wrong, not who is causing it.
MOST ABUSE COMES FROM COMPROMISED ACCOUNTS, NOT MALICIOUS CUSTOMERS
Automate suspension above thresholds, because damage occurs in minutes. And give the customer specifics — vague notices produce arguments rather than fixes.
ADDRESS REPUTATION IS SHARED BY EVERY CUSTOMER
Separate outbound mail onto dedicated addresses, fix causes before requesting delisting, and check the history of any address range before using it.
THE CONTROL PANEL IS THE PRODUCT AND ALSO A PRIVILEGED SYSTEM
A vulnerability in it compromises every account. Patch promptly, and never hand-edit configuration it will overwrite.
SUPPORT CAPACITY IS FREQUENTLY THE REAL LIMIT ON GROWTH
Measure which issues generate most tickets — fixing the top cause reduces load more than adding staff.
BE HONEST THAT SHARED HOSTING ON ONE MACHINE IS NOT HIGHLY AVAILABLE
Offer arrangements that genuinely provide it, priced accordingly, and publish what you actually commit to.
