Most women in prostitution in Germany come from Eastern Europe. They come to Germany with the hope of freeing themselves from poverty through prostitution. Most of the time they have no school or vocational training and so they can only find poorly paid work in their home country or are unemployed. A bitter reality awaits them here.
They need at least seven suitors a day (depending on where they work) to barely get by financially. For example, there are unacceptable market laws, high dumping prices, which lead to extremely high numbers of clients. Women are also often forced to have sexual intercourse without a condom due to financial hardship.
They send a large portion of the proceeds to family members back home. To get out, they would have to overcome language barriers, have identification documents, health insurance and find an apartment instead of living in a brothel room. This requires money and a new life plan. Women usually don't have either.
So they remain trapped in prostitution.
Poverty in the home countries is also a compulsion. This is not the only reason why the boundaries between the terms “poverty prostitution” and “forced prostitution" often are fluent.