One of the benefits of using Drupal for your web site is that you do not need to pay your service provider or web design company money to make changes once the site has been completed. Many service provider convince their customers that Drupal is so complex that its best left to them to make changes. Although there is some element of truth in the fact that someone coming to Drupal for the first time might be a bit overwhelmed, the fact of the matter is that this is more often than not a ploy to lock the customer into that provider.
Drupal Site Maintenance can be Mastered by Anyone
Once the major site development is done, Drupal is powerful enough to allow anyone, including a person with limited web knowledge, to make changes and update their site. A few hours is all it takes to master the Drupal basics, like adding or editing content and changing menu items or menu locations.
Even more "complex" tasks such as adding modules or creating forms to capture information do not require more than a day or two of training to master.
Drupal Sites Are Portable!
Beside convincing customers that site maintenance is best left to them, service providers also tie customers into their services by getting customers to host with them to "enable us to update the site with patches". Whilst it is true that customers would probably like to outsource this functionality, many service providers do it by hosting all their Drupal sites on one instance. The upshot of this is that if you try and move your site, or take over the maintenance yourself, you are told that it cannot be done. In essences, you are locked into hosting with them and all the development work you paid for is not transferable. If you do decided to outsource the patching and upgrading of your Drupal site to a service provider make sure you get them to sign that the site belong to you and you are free to move it should you so desire.