1. Gather all relevant information on the vendor's performance, including contracts and SLAs. 2. Review performance reports to identify shortcomings. 3. Analyze data to pinpoint specific issues such as punctuality, quality, or communication. 4. Use this understanding to address issues directly with the vendor. 5. Base discussions or negotiations on the gathered information to improve service delivery.

To address subpar vendor performance, conduct a thorough assessment, communicate concerns, negotiate terms, set deadlines, explore alternatives, and document everything. This will help improve vendor performance and ensure they meet required standards.

Turning around a situation with a vendor delivering subpar services requires a firm yet collaborative approach. Begin by clearly documenting the specific issues and referencing the agreed-upon service level agreements (SLAs) to provide a factual basis for your concerns. Schedule a formal meeting with the vendor to discuss these issues openly, focusing on the impact their performance is having on your operations.

Vendor's SLA must be measured against scope and KPI's agreed upon. It is must to have all SLA's to have Incentives and Liquidated Damages defined. This must be measured each month and any shortcomings must be notified to vendor in written form. Initially there should be soft talks followed with warning and as a last resort imposing penalties.

Dialogues should be a continuous process and should not be necessarily done only when the vendor is slipping against the target. We should be rather appreciating any positive developments done by the vendor. May be certain issues vendor is not able to communicate through which should be addresses by having initiating trust building measures.

Expectations set must be documented and reviewed from time to time and appropriate measurables are defined to and checked where we stand at regular intervals. Generally in a facility there are multiple vendors performing each type of work and there are times when certain activities are interdependent. Here Client has to come in between and take the task forward by way of proper alignment.

Simply stating that the work is sub-par, or does not meet your standards is not enough. If you've provided the standards in writing, and clearly identified deficiencies, and there is still a problem, more formal action will likely be necessary. Start with a collaborative approach. Sit with the vendor and have some honest brainstorming regarding how to get things to improve. It is easy to lean toward punishment, but that may not resolve the problem. Agree together on next best steps, put it in writing with timelines, responsibility and definable goals. You should also have defined the escalation path beyond this step, and possible outcomes. The goal is to finish the work on time, on budget and at the acceptable (defined) standard.

Renegotiating terms while the contract is up and running is generally not possible except there are things which have fundamentally changed. Certainly this comes with discussing all interlinked terms and conditions that were previously agreed upon. This must be noted that this most of the time given more leverage to the vendors rather than this going in favour of the client.