overhasty (
http://definr.com/overhasty)
adj : done with very great haste and without due deliberation;
"hasty marriage seldom proveth well"- Shakespeare;
"hasty makeshifts take the place of planning"- Arthur
Geddes; "rejected what was regarded as an overhasty
plan for reconversion"; "wondered whether they had been
rather precipitate in deposing the king" [syn:
hasty,
precipitate,
precipitant]