It is the extremes that place excessive and often unexpected demands on systems poorly equipped to deal with those extremes. (dotearth.blogs.nytimes.com)
But research indicates that when couples encounter such stresses or unexpected demands on their energy, their satisfaction with their relationship declines and their risk for breaking up increases. (nytimes.com)
«In fact, this approach presents large, often unexpected demands for organizational capacity.» (gse.harvard.edu)