Supposedly we are in the midst of a terrible shidduch crisis. If you're looking for an explaination as to why there is a "crisis" you have to ask multiple people, or else you won't get a good laugh out of it.
Some person had nothing better to do and he came up with a mathematical equation as to why there is a shidduch crisis. He came up with this entire concept of there being more frum girls than guys. He has many followers. They all firmly beleive in this numbers crisis. At one point these crazy nuts even created NASI (North American Shidduch Initiative). NASI is in organization that was formed to give incentive to shadchanim to set up couples in which the guy were either older, but very close in age to the girl, or a tad bit younger then her. If the couple got married, she got paid in accordance to the age difference. "Unfortunately" for these loonies, the fund to pay for this Initiative went dry... so now they have to do things on their own.
These crazies forget one thing, while their world supposedly has more girls other frum worlds have more guys! There is the "out-of-town" world, which is like the entire world grouped into one category, and then there is the "BT" world. BTs tend to have more guys than girls. For whatever reason there are more guys becomming frum than there are girls. But who the heck cares about this stuff anyway...its a crisis. Being picky is good stuff.
Picky I say?
The second reason you may hear as to why frum people have a shidduch crisis is because of pickiness. They claim that people focus too much on unimportant things, and then break up even though there is still a lot of potential for the relationship to work out.
So, I've got a story on pickiness.
Someone tried to set a girl I know up. She always said she wanted a guy who only learned. The guy they wanted to set her up with was in the process of becomming a Rabbi and he planned on being a Rabbi for a living. She rejected the date.
When I heard about that, I was extremely shocked, WTH is the difference between the two, except for the fact that a Rabbi may actually get a job at some time in their first few years of marriage, whereas the Kollel yungerbum will sit on his a$$ and be as useless to society as bicycles are to fish.
While mathematically in certain areas shidduchim may be complicated, and some people are overwhelmingly picky about stupid things, I don't think the overall problem with shidduchim is anything other than stupid indoctrination by the yeshiva/seminaries. Had these dumb schools not messed with people's heads, they'd be more practical and more mature, and therefore more able to have a well adjusted-normal dating experience, hopefully one with a positive outcome as well.