The use of resources should be sustainable.bcoz limitless usage of the resources may lead to the total completion of that resources.resources are renewable and non-renewable. Some resources can be produced again and some can't be. But the more usage of resources leads to completion of those all resources.those resources become extinct. And we may suffer frm these activities.non renewable resources are fossil fuels so these are limited and we have to use these in a limit.renewable resources are water,air etc... These are limitless but we have to use in a limit so that we can give these to the next generations.
Hope this helps u.