I see your distinction, but how much slack you think you have is necessarily a judgement based on how demanding your environment is. People mis-estimate that regularly, and it changes over time anyway. If it feels wrong to have available resources that you’re not using, it may be that you just need to lighten up. It also may be that you’re correctly, if not necessarily consciously, perceiving that your environment is competitive and you actually do need to buckle down (or go somewhere else). These are different problems with different solutions but similar symptoms.
I see your distinction, but how much slack you think you have is necessarily a judgement based on how demanding your environment is. People mis-estimate that regularly, and it changes over time anyway. If it feels wrong to have available resources that you’re not using, it may be that you just need to lighten up. It also may be that you’re correctly, if not necessarily consciously, perceiving that your environment is competitive and you actually do need to buckle down (or go somewhere else). These are different problems with different solutions but similar symptoms.