Ban activity, sale, service etc that is undersubscribed is not bought or used by enough people 〔活动等〕参与人数不够的；〔商品、服务等〕客户太少的OPP oversubscribed
Examples from the Corpus
undersubscribed• And, I believe, science courses continue to be undersubscribed in our universities.• The placing and rights issue to fund the acquisition were undersubscribed, with 61.2 percent of the rights issue taken up.