Yes ...
A balcony at our complex is directly over the living room of the apartment below.
The balcony flooded and it was also causing dampness issues in the living room below.
The builder, twelve years ago had laid inadequate insulation on the concrete floor of the balcony. Also they had not sealed the balcony floor with waterproofing material. The slabs on the balcony were laid on plastic holders directly on top of the inadequate insulation which like just like broken up pieces of styrofoam.
The gravel use for the side channels was a slight upgrade on sand.
The down pipe inlet was unprotected .. it had no grill.
We removed all materials from the balcony.
We sealed the flooring and up a distance on the walls with rubberised paint
Proper insulation was laid on that
Pea gravel was used as a base for the slabs and as filler material for the side channels
A met grill was fixed to the down flow outlet and some larger stones on top of that.
The job was perfect
It is important not to allow top soil from plant pots to spill on balconies.
It is important not to allow weeds to grow between the slabs or in the side channels.
It is important to ensure that the copping stones do not gather moss and that the pointing is repaired as necessary.