Integrating Zendesk means getting tickets in front of the people who do not work in Zendesk: engineers in Jira, account owners in Salesforce or HubSpot, and teams in Slack. What breaks is the boundary between internal and public, where one wrong default sends internal notes to a customer, along with identity matching to CRM records, trigger loops, and per-minute API limits during a ticket storm.
Zendesk is where customer support happens, and its integrations exist so that support does not stay a silo.
The most common need is escalation. A ticket becomes a Jira issue, and when engineering moves it through its workflow the ticket and the requester are updated, with many tickets able to point at one bug. The second is customer context. Account owners in Salesforce or HubSpot want open tickets, CSAT and SLA breaches on the account without opening Zendesk, and agents want lifecycle stage and open deals without leaving their desk. The third is attention: new tickets, priority changes and SLA breaches routed into Slack, one thread per ticket, with threaded replies going back as internal notes or public replies.
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