Remote viewing experiments historically suffered from poor controls and challenges in repeatability.

Many early remote viewing studies lacked strict experimental controls such as double-blind protocols, proper randomization, or adequate statistical rigor. This made the results vulnerable to biases, sensory leakage, or inadvertent cues. Attempts to replicate findings under more rigorous conditions often failed, undermining claims of psychic perception. Some proponents developed stricter blinding methods, but skepticism about the phenomenon's reliability remained widespread.