A __________ investigation can sometimes yield new facts, but typically organized once are more successful.
Explanation: Meandering (as adjective) = proceeding in a convoluted or undirected fashion.
Timely (as adjective) = done or occurring at a favourable or useful time; opportune.
Consistent (as adjective) = acting or done in the same way over time, especially so as to be fair or accurate.
Systematic (as adjective) = done or acting according to a fixed plan or system; methodical.
Therefore, meandering is correct choice, all other options are similar to the word organized.
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