Sustainability tech has gained attention, with projected funding reaching $75 trillion by 2050. However, venture capital investment in this sector has declined since 2021, as investors often apply metrics suited for faster-growing tech sectors, leading to a mismatch in expectations. Many sustainability startups face long fundraising cycles and struggle to secure financing despite validated technologies. To improve outcomes, investors should rethink funding models, provide actionable support, and adjust evaluation metrics to align with the unique characteristics of sustainability technologies. Adapting these approaches is crucial to fostering innovations that address pressing environmental and social challenges.