When writing an application, you are basically performing marketing, promoting the brand of ‘YOU’, your knowledge, skills, and experience to the employer.
An employer can only judge what you can achieve for their business by what you have previously accomplished for other companies.
Other applicants write big lists of what they have achieved in their employment, thinking they have created a great application. The issue is they never got invited to attend that interview because all they did was write a long list.
You need to focus on what is in it for the employer with what you have achieved in your employment history. Make the employer believe your statements about what you can do for them and their organisation. In order to do this, you need to really sell your achievements and experience.