What they do is set single men up with other single men on many occasions, while attempting to cut them off from the opposite sex. Several program-wide instances of this run through the Tower--the Pioneer Assist program, the Bethel roommates, and the reading assisting school they set up in 1977 are key examples of widespread incidents where two people of the same sex are paired off. If they are also cut off from the opposite sex to a sufficient degree, then they could become infatuated with each other. Some are more susceptible to this as it is; the more they can be cut off from the opposite sex, the worse the problem is likely to be.
And what they did to me was, besides cutting me off from the opposite sex as best they could, was to always have me work with the same brother in service for long periods of time. This could run for years at a time. They would basically have the same brother, who became a regular pioneer, always work with me when we were out in service. And later, after this brother died, it was only a matter of time before they found another brother for me to work with consistently. That didn't work out because I started not going out at all.
These are examples of homosexuality that happens when two same sex people are paired off consistently (in this case, I didn't actually become active as a homosexual). This also happens in the military when the sexes are separated and the boys are all put aside in the same unit without any opposite-sex company. At least in the military it is accepted--in the Tower, it is not.
Notably, there is another potential cause for homosexuality to develop. This happens normally at or shortly before puberty, and the person does not outgrow it. Notably, the Watchtower Society is great at stopping people from growing up (note that they treat the members like little children: the "one towel" rule is a prime example). Under these circumstances, pair two brothers on a semipermanent basis, and watch out! There is a fair chance that one or both will become infatuated with the other. This is a normal reaction to an abnormal situation.
Of course, some homosexuality is genetic or the result of hormone imbalances. This is not the issue here, since it will happen whether or not it is encouraged. What is at issue is that the Watchtower Society actually provides circumstances that can lead to opportunistic homosexuality, at least in feelings if not actually acted out. And, for a society that is against it, that makes them hypocrites. And any counsel that cuts off the mixing of the opposite sex and/or encourages the same men to always be together can fit into this as promoting something that they are supposed to be against.