The purpose of the quality theme in PRINCE2 is to ensure that the project outputs meet the requirements that have been agreed upon. This theme guides the processes and activities required to verify that deliverables are fit for purpose and meet the standards expected by stakeholders.References: = PRINCE2 7 Foundation handbook and online resources

The principle of 'tailor to suit the project' in PRINCE2 emphasizes that the methodology should be adapted to fit the project's environment, size, complexity, and specific requirements, rather than applying it uniformly. This flexibility ensures that PRINCE2 can be tailored to any type of project, whether small or large, simple or complex, in any industry.References: PRINCE2 Foundation Manual

The 'Managing a Stage Boundary' process is used near the end of each stage of a project. This process includes the review of the current stage, preparation for the project board to authorize the next stage, updating a project plan, and, if necessary, updating the business case and project initiation documentation.References:
= PRINCE2 7 Foundation handbook and online resources

In the 'planning' technique, a team manager should break down the cost of delivering a work package during the 'Preparing estimates' step. This involves estimating the resources and time required to deliver each component of the work package, which are critical for budgeting and resource allocation. References:
PRINCE2 Foundation course material on planning techniques and project management documentation.

According to PRINCE2, a project outcome is defined as the result of the change derived from utilizing the project's outputs. Outcomes are what the project seeks to achieve which may involve a change in the way an organization operates. References: PRINCE2 Foundation official guide and study material.