In generating small amplitude guided waves in elastic materials for diverse experimental investigations, one is faced with several limitations. This paper examines the limitations arising from the inherent nature of materials not to withstand, in some cases, the existence of guided waves either in certain finite frequency ranges or in the whole frequency spectrum. The material constants as well as the stress conditions in the materials play a key role in allowing the experimental generation of guided waves. The model examined in this paper incorporates a small layer either imbedded in a host material or a small surface layer overlying a host material, both materials in general being pre-stressed. The analysis defines limitation regimes where experimental generation of guided waves would not be possible. These regimes are given explicitly in terms of material constants and stress conditions.