Considering only the monetary costs in a cost/benefit analysis is not advisable due to several reasons:
1. Limited Perspective: It ignores broader impacts beyond immediate expenses.
2. External Costs: Hidden costs to society or the environment may be overlooked.
3. Long-Term Effects: Decisions often have lasting consequences beyond short-term financial gains.
4. Intangible Benefits: Non-monetary advantages like well-being are hard to quantify.
5. Opportunity Costs: Valuable non-monetary opportunities might be missed.
6. Complex Interactions: Interdependencies between factors may be disregarded.
7. Ethical Considerations: Ethical values can be sidelined in purely financial analyses.
8. Stakeholder Impact: Effects on others might not be taken into account.