Does a project charter need to be constructed for every project that is small and usually executed by the organization?
Although a project is a unique endeavour there are in some organizations certain project types that are always executed (for example in a telecommunication industry the expansion of capacity of communication nodes is always seen as a good business opportunity and the proposal work is always done).
The charter in this case is a pretty standard document stating the business opportunity and the usual constraints that the project must take into consideration. Only a certain level of review needs to be done by the sponsor to acknowledge that the unique characteristics of this project are stated in the charter. This is a very quick task but with a very high return since at this phase the sponsor can alert the project manager for risks that must be accounted for during the planning phase.
As we all know as soon as a potential problem is uncovered more likely is that the cost of treating it will be lower. In the software industry the cost at the early phases can be from 10 to 5 times less the cost of handling a problem when it is too late.