One way people make decisions is by not making them.
Shall we buy a new car? A family can probably save some money, at least for the moment, by not making that decision.
In the immigration field, USCIS (in recent years) has followed this policy differently for three migrant groups: potential voters, potential alien investors, and potential green card applicants seeking their credentials by claiming to be a crime victim or a relative of one.
Let's start with aliens seeking those dubious U visas, for crime victims. Why U.S. law gives green cards to people because they have had the misfortune, or the alleged misfortune, of an assault or a robbery, is beyond me. USCIS must have the same reaction and it has shown this by dragging its feet on deciding U visa petitions for this benefit.
According to a standard USCIS workload measuring system (described below), at the end of calendar year (CY) 2015, there were 108,623 pending U decisions. The most recent data, for CY 2019, that is four years later, shows the number had climbed to 257,837. In many of these cases the proposed beneficiaries were illegal aliens who had a clash with (perhaps) other illegal aliens. I agree with the apparent USCIS policy of not rushing too much with this population; many if not most of them seeking a backdoor to amnesty.
Using the same data system, and the same two dates, let's see how USCIS handled backlogs of applicants in two other benefit programs, one for immigrant investors and one for naturalization (i.e., potential voters).
At the end of CY 2015, which was the start of the last year of the Obama administration, there were 21,988 rich aliens seeking decisions about their applications to become (eventually) green card holders by making a major investment in a DHS-approved, but not guaranteed project, often in big city real estate. Advancing their causes were the urban middlemen who profited from the EB-5 program. That may relate to the fact that four years later the number of applicants in the pending file was down to 17,468.
Meanwhile, a far larger group of aliens (of all economic levels) have filed naturalization applications, wanting to become citizens and, in many cases, wanting to vote. The number in the pending category, using the same reporting system, has grown by a quarter of a million in the four-year period we are studying: There were 384,850 at the end of CY 2015, and 649,021 at the end of CY 2019.
Did this have anything to do with the administration's other efforts to discourage voting, such as the president's unhappiness with postal ballots? I will leave that to the reader to decide.
The data system is entitled "Number of Service-wide Forms Fiscal Year to Date by Quarter and Year", and its most recent report covers the three months ending December 31, 2019. We described it earlier and its various reports can be seen here.