Why we need vod and aod to make stainless steel? what is carbon content of stainless steel?

Carbon is the only impurity which removed by gaseous form (2C + O2 = 2CO(g)). Other impurities are forming solid oxides which goes in to the slag. So, CO gas doesn’t affect the slag volume. At the same time because of it is gas, it much more depends on pressure. In LD steel making at 1600°C and 1 atm and 800 ppm oxygen level we can remove carbon upto 250 ppm. Below that, it is thermodynamically not possible. If you want to reduce further what should we do? By reducing partial pressure of CO gas we bring down carbon content blow 250ppm. So, how to reduce partial pressure of CO gas? That is why we are going for AOD and VOD process. We can’t say generally carbon content in stainless steel. For example 304L austenitic stainless steel contains 0.03 percentage carbon and 304 stainless steel contains 0.08 percentage carbon. So carbon content is depends on grade.