How would you explain the causes of sex trafficking and its rapid growth in the last few decades in certain countries? Please consider it in relation to poverty, failed states, corruption, organized crime, insufficient resources of police and government in source and destination countries, culture, sophisticated recruitment strategies, and/or high demand by men to exploit and abuse women.

Human sex trafficking has been an issue since the dawn of civilization, most often materializing in a migration from impoverished or less affluent nations, where flesh is one of few precious commodities, to wealthier, more affluent nations, where customers are willing and able to pay for such a commodity. The epidemic is often seen as a symptom of growing poverty conditions; however, the spread of Western-style capitalism throughout the nineteenth, twentieth and twenty-first-centuries has actually resulted in reduced levels of poverty globally and therefore cannot be honestly targeted on a macro-level as the primary culprit for the recent increase in sex trafficking.
Yet, on a micro-level, there is certainly evidence that poverty remains a contributing factor. This is especially prevalent when assessing the increased levels of trafficking from specific, isolated countries, where factors such sa totalitarianism, political corruption, organized crime, and anti-capitalistic economic controls have left greater numbers of their citizens impoverish than in past decades. Famine, disease, economic desperation, and other fears are strong inducements for otherwise rationally-minded citizens to allow themselves to be exploited through the sex trade.
In addition, there are often insufficient law enforcement resources in both the country of origin and the destination country, which sex traffickers can use to their advantage, especially when they see the situation as an opportunity to increase the size of their operations. Countries of origin already facing economic strife often have little to invest in hiring and properly training the personnel required to stem the flow of such operations, while low pay for the few personnel currently in those positions means pay-offs and bribery are far more rampant. In the destination countries, politicians use the issue (and the larger related issue of illegal immigration) as a chess piece for other political objectives, which often leads to far fewer resources being assigned to deal with the problem than an unbiased approach would warrant.
However, an even greater physical presence of law enforcement in destination countries alone would not be sufficient to stem the tide if those personnel were not adequately trained in the new techniques, technology, modes of transport, and communication methods traffickers are using today. The ever-evolving world of technology—especially the internet and the fact that it's now globally accessible—has allowed more traffickers to reach a much greater audience online and to do so through higher levels of anonymity.
According to a 2005 US Census Bureau survey, 24.5 million children were using the internet at that time and approximately 20% had received some sort of online sexual solicitation. Subsequent studies have shown these numbers have steadily risen since then. Law enforcement not only has more difficulty locating these traffickers but also pinning down eyewitnesses and hard evidence to be used in investigations. Online sex trafficking also increases the transitory nature of the cases, spreading them across multiple jurisdictions and making it less likely that different law enforcement groups will be able to coordinate their efforts.
Other factors have also contributed to the increase in trafficking over the last several decades. Traffickers have become more savvy in their recruitment methods through trial-and-error, creative propaganda that has perpetuated the myth of sex trafficking as a "victimless crime" (which can be disseminated widely and rapidly through online means nowadays), and greater understanding of psychological manipulation methods that leads victims to become willing participants. They have also learned to capitalize on major events in areas like sports and entertainment. According to Forbes, 10,000 prostitutes were brought to Miami for Super Bowl XLIV in 2010, and there were 133 underage arrests for prostitution at Super Bowl XLV in Dallas in 2011.
Trafficking in women is especially profitable—some suggest far more so than drugs or firearms since the same woman can sold over and over—and more outsized profits are being reaped as wealthy nations grow wealthier, with more disposable income to spend on such a commodity.
https://atlantadailyworld.com/2013/09/19/4-reasons-why-human-trafficking-is-on-the-rise/

https://www.huffpost.com/entry/human-trafficking-increasing_n_6425864