Fester

Americans – both team leads and team members – almost always prefer a suboptimal conflict resolution reached in a timely manner over an optimal resolution arrived at late. Americans refer to conflicts which fester. 

fester: to become painful and infected; to become worse as time passes; to cause increasing poisoning, irritation, or bitterness; to undergo or exist in a state of progressive deterioration; to make inflamed or corrupt; “We should deal with these problems now instead of allowing them to fester.”

First known use 14th century. Synonyms: break down, corrupt, decompose, disintegrate, decay, foul, mold, molder, perish, putrefy, rot, spoil.