Develop criteria for key account status
Selecting key accounts from your list of all accounts may be the most difficult part of key account management. After all, every account is key, right? Wrong, the single biggest mistake is including too many accounts on your list. When that happens, no account gets what they need. In other words, it's better to limit rather than dilute. Now, it's tempting to say your key accounts are your biggest accounts in terms of revenue, but be careful, this can lead you down the wrong path and you'll end up overlooking accounts with much more potential for your company.
To select key accounts, you need to develop criteria. Now, a mistake, at this point is to develop too many criteria. Trust me, you don't need that many. Three or four is a good rule of thumb. The best starting point to develop key account criteria is to look at your company's strategic plan. Where is your company headed in terms of profitable growth? Are there new markets your company is trying to penetrate? Perhaps a new geography like Asia, or perhaps a new industry like health care?
Source: https://www.linkedin.com/learning/key-account-management/develop-criteria-for-key-account-status