A BBC journalist writes about the dangers and consequences of scientists who fabricate their results.
I've written about a similar article and topic here, discussing the shortcomings of peer-review, which ultimately reflect on the self-regulated industry which is scientific research.
Jardine, the BBC writer, stresses the pressure to fabricate could be credited to the competition for funding, especially in regards to finding "big" breakthroughs and making spectacular discoveries. As a grad student, I can cite another potential source.
It's not just that funding issues put pressure on researchers to produce results. Professors put pressure on their grad students to produce results, in the form of "If you don't publish, I'm taking away your funding and you'll never get your Ph.D." Now, I imagine that most professors can spot any attempts to "enhance" results, but for all of the thousands of grad students across the sciences performing research, I find it perfectly believable that some students have published erroneous results. Whether that means data is exaggerated or completely fabricated, I'm certain it happens at a rate most would rather not think about.
As far as a solution goes, I have none. Peer review is vulnerable to problems, but the truth is that no other system exists to prevent bad science from being published or funded. As long as there is money in science (whether from funding, fame, or success) there will be people who play fast and loose with their results.