For those who specialize in scientific research projects, they are always, and constantly looking for more research money. If they fail to impress those that might be giving them the money in grants, then they have to stop operations and stop their research. Often, the people that are giving the grants are politically motivated and a desire specific outcomes of the research. Most researchers get upset with these things because they wish to do ethical research, and yet, at some point they need to do what is most prudent to keep their research facility going.
When dealing with specific research, or researching a specific set of circumstances, often a researcher might have an observation that they were not expecting, and if that particular observation is not in line with their research or their desired outcome to please their clients, they will disregard it. Their basic understanding is that if it is outside the scope of the experiment, it is irrelevant to the paper that they will be writing.
And yet, an ethical observer might say that such observations should be known to all, and they are important to other researchers in the future, not to mention that such observations if ignored cover up the truth. Of course, this is just one type of ethical question that comes into play while doing scientific research for specific clients that have a specific agenda.
It is often also noted that research is stopped halfway through when certain observations are found, and the research is then re-focused in a different direction, one which might yield a slightly different observation or prove inconclusive, which is often okay with the client.
However, these things are indeed problematic and if we cannot get ethical researchers, or if they are simply after the money then their research is of no value to the human race and they are of no value to science in my personal and professional opinion after 20 years of observation of these types of things. Please consider all this.