More precise explanations are needed to better understand why public green spaces are diminishing in cities, leading to the loss of ecosystem services that humans receive from natural systems. This paper is devoted to the incremental change of green spaces—a fate that is largely undetectable by urban residents. The paper elucidates a set of drivers resulting in the subtle loss of urban green spaces and elaborates on the consequences of this for resilience planning of ecosystem services. Incremental changes of greenspace trigger baseline shifts, where each generation of humans tends to take the current condition of an ecosystem as the normal state, disregarding its previous states. Even well-intended political land-use decisions, such as current privatization schemes, can cumulatively result in undesirable societal outcomes, leading to a gradual loss of opportunities for nature experience. Alfred E. Kahn referred to such decision making as ‘the tyranny of small decisions.’ This is mirrored in urban planning as problems that are dealt with in an ad hoc manner with no officially formulated vision for long-term spatial planning. Urban common property systems could provide interim solutions for local governments to survive periods of fiscal shortfalls. Transfer of proprietor rights to civil society groups can enhance the resilience of ecosystem services in cities.