What is a drawback of "single-scores" or "single-proxy" Life Cycle Assessments (LCAs)?

Single-score or single-proxy life cycle assessments (LCAs) simplify complex environmental impacts into a singular metric. While this can be beneficial for providing a quick overview or easier comparison between products or processes, a significant drawback is that they can lack transparency. By condensing various environmental factors—like carbon emissions, water usage, and resource depletion—into a single score, critical nuances and individual contributions of different environmental impacts may be obscured.

This lack of transparency can make it difficult for stakeholders to understand how specific decisions influence outcomes, potentially leading to misinformed conclusions about sustainability. In contrast, multiple-factor LCAs allow for a more detailed analysis, enabling clearer communication of the various environmental impacts involved. This depth of information is particularly important for stakeholders who need to understand the specific trade-offs and implications of their choices in sustainability practices.