Cold extraction is usually preferred for a raw extract, that is when we want as many compounds as possible. A hot extraction like soxhlet or decoction may be useful to concentrate or even recover certain kind of metabolites.
However it comes at the cost of other compounds, that may be hydrolyzed or thermolabile. Therefore one should always make a cold extraction while working on new extracts.
Cold extraction is experimentally better procedure for a new plant extract. Because some plant extract does not suit hot extraction for heat sensitiveness.so we prefer cold extraction for all plant extract.