Most agencies are project-based. They design the site, build it, hand it over, and close the file. The site is now the surgeon’s responsibility — hosting, security, maintenance, updates, the periodic redesigns a site needs to stay current. This is rarely explained clearly during the sales conversation, and surgeons rarely think to ask.
The practical implication: a site built by a project-based agency has no one responsible for it the day after launch. Problems are handled on an ad hoc basis, usually at additional cost, usually with some delay. Features and content that need updating get deferred because there’s no structure in place to handle them efficiently.
Before signing anything, ask explicitly: what does your involvement look like after the site launches? What does maintenance cover? Who do I contact when something needs changing? The answers will tell you whether the agency sees this as a project or a relationship.