Cheap imported clothes mean that people can save some money by buying these imported products rather than locally produced items. But, the costs associated with such cheap imported clothes generally far outweigh their benefits. Some such costs include, low quality, lost jobs, environmental neglect, labor concerns, sustainability issues, unfavorable balance of trade, etc. Many such low cost imports are of poor quality and may not last long, thus requiring purchase of similar items after some time. Imports from China are typically suspected of low quality. Imports of cheap clothes causes business loss for local companies, which results in job loss and hence direct adverse impact on local community. Low cost production, typically, comes at the cost of environmental damage (in terms of water and outdoor and indoor air pollution) and poor production practices (including low wages, poor working conditions and exploitation of workers, including child labor). Low cost imports also results in profits for foreign companies and their prosperity, while causing higher share of imports, as compared to exports. This causes unfavorable balance of trade.
All these costs add up and far outweigh the benefits obtained by importing cheap clothes (and other products).
Hope this helps.