this is over time. the individual misses only result in a small ulcer on the arm. The vein is important because circulatory vessels are very resilient, much like rubber hosing. However, even prolonged intravenous use will result in destruction of the vein. This picture is also a particularly bad case because the ulcers are very prone to infection, the blackened flesh on the upper part of the arm in this photo is necrotic flesh from gangrene.