No seniority means that no preference, priority or precedence is given to those of the same rank for simply providing a longer service to the company. This philosophy is used due to the performance-based philosophy, this ensures people are treated fairly and rewarded based on their efforts, not the length of time that they have served; this is also good for morale.
100% promotion within means that all positions available within the company are given to those working within the company and people are not recruited externally to fill positions. Statistics show that it is better for relationships and performance of Individuals. It is good for morale, as no one will be asked to do something that a more senior person was not able to preform or not willing to do by himself or herself. This method is also much more cost effective as the chance of failure is highly reduced.
100% percent performance based mean all compensation, rewards and promotions are given based on individual performance. This removes politics and seniority from the company, which is also great for morale and creates job security. It means that each person was rewarded for their position and pay based on their work ethic or skill. The risk of failure for the company is significantly reduced.