There are many synonyms for the phrase "badly thought out" that can convey the various degrees of poor planning or execution. Some of the common synonyms include poorly planned, ill-conceived, haphazard, ill-advised, or slapdash. These terms suggest a lack of forethought, organization, or strategy, and may result in inefficiency, inadequacy or failure. Other similar phrases that convey a similar sentiment include careless, reckless, thoughtless, impulsive, or rash. Effective planning and execution are crucial for success in any project, and using these synonyms can help identify areas that require further analysis, evaluation or re-evaluation to prevent poor outcomes.