Slides are convenient because there is no heel strap to fasten. That same open back changes how the shoe follows your foot. For a day involving a lot of walking, the question is not whether slides are fashionable or sandals are sensible; it is whether the particular pair stays secure during your actual movement.
Try both options on a clean indoor route with turns and stops. Notice whether you shorten your stride, grip with your toes, or repeatedly reposition the foot in the slide. These observations matter more than a comfortable first impression while standing still.
An adjustable sandal may provide more ways to secure the foot, but it can also place a strap in an uncomfortable location. Check the heel, ankle, and forefoot separately. A strap that rubs immediately is not improved by the general idea of greater security.
Compare the base of the shoe
Footbed length and shape still matter in both designs. The toes and heel should sit comfortably on the usable surface rather than at an unstable edge. A molded contour that does not align with your foot can feel intrusive even if the straps fit well.
Look at the sole and the maker's intended use. A deep tread pattern does not guarantee performance on every wet pavement or smooth indoor floor. If the day includes a specialized activity, choose footwear intended for that activity rather than extending a casual style beyond its role.
Weight can affect the way an open-backed shoe moves. A heavy slide may require more effort to keep with the foot than a lighter one, but construction and fit vary. Judge the actual pair rather than assuming all chunky styles behave the same way.
Plan the whole day
Think about stairs, transit, carrying bags, and the distance between breaks. A slide that is ideal for a short trip from a room to a pool may not be your preferred shoe for hours around a city. Conversely, a simple sandal can be unnecessarily complicated for a brief indoor use.
If you already own both, take the pair that lets you walk naturally and reserve the other for the role it serves well. A new purchase should solve the specific attachment, fit, or comfort issue you have identified, not merely replace one style category with another.
