Which aspect is essential for determining the success of electrical wiring installation in damp locations?

The essential aspect for determining the success of electrical wiring installation in damp locations is protection against moisture. This is crucial because electrical wiring in environments where moisture may be present is highly susceptible to corrosion and short-circuiting. Using wire that is specifically rated for damp locations ensures that it is adequately insulated and shielded from moisture ingress, which can lead to safety hazards such as electric shocks and fires.

While the correct wire type is important and plays a role in overall installation integrity, without proper protection against moisture, even the best wire can fail in a damp environment. Installation height can also influence the effectiveness of the installation, as higher placements may reduce exposure to water accumulation, yet it doesn't address the immediate protection required against moisture itself. Insulating all connections is vital for ensuring safe operation, but it again is rendered inconsequential if there is no initial mitigation against moisture exposure that could lead to those connections failing. Therefore, focusing on moisture protection is central to ensuring long-term, safe operation of electrical systems in damp conditions.