Imprudent implies a judgement of someone's actions as negative because they lack careful thought. His imprudent remarks about the boss's strategy could get him in trouble.
Pro Tip 2/3
Risk of Harm
Use 'imprudent' to suggest that an action could likely lead to harm or a bad outcome. Driving without a seatbelt is an imprudent choice.
Pro Tip 3/3
Lack of Planning
'Imprudent' can describe actions done without planning ahead or considering the consequences. Buying a car without a job was an imprudent decision.