How can I express these points without being unprofessional?

Regarding my cover letter/the questionof why you want to work there

I want to (low-key) mention that I am tired of working with people who don't care. People who do everything they can to avoid doing certain parts of their job, and leave it for me to pick up the slack (because if I don't, nobody will and I will have no room to do my own job if I don't pick up their slack). This my sound like a stupid question but I am extremely tired of this and it is the main reason, aside from money, that I am trying to leave a physically active job for an office job.

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