Maybe the bone of contention is less about levels per se than it is about the suggestion of hierarchy.
If so, the critics may have a point. Although people often summarise the MLP as ‘micro-meso-macro’,
the levels are defined as referring to different degrees of structuration of local practices, which relate
to differences in scale and the number of actors that reproduce regimes (and niches). Levels thus refer
to different degrees of stability, which are not necessarily hierarchical. This is a deviation from earlier
MLP-work, which used the notion of ‘nested hierarchy’. While this is an attractive metaphor, most
niches do not emerge within regimes, but often outside them (although niche actors are usually aware of regime structures). While the socio-technical landscape is an external context, the relation with
regimes (and niches) is not necessarily hierarchical (just as one would not characterize soil conditions,
mountain ranges and rainfall patterns as hierarchical structures for biological evolution). So, perhaps
we should consider dropping the ‘hierarchy’ notion in the MLP.