"Poor lookout" can have various synonyms. For instance, one could say "negligent surveillance" or "inadequate watchfulness". Another synonym could be "careless observation" or "short-sighted monitoring". Similarly, "impaired vigilance" or "deficient attentiveness" can also be used in place of "poor lookout". The term "lackluster alertness" can also serve as a synonym for "poor lookout". These synonyms convey the message that there has been a failure to observe or monitor something properly, which can result in negative consequences. It is always advisable to remain vigilant and alert, and to maintain a good lookout, especially in situations where safety is of utmost importance.