I’ll name 2 of the reasons, ignoring things like Trump not respecting the rule of law.
(1) Sadly for democracy, it has become standard practice in GOP-controlled states to do everything possible (until the courts order them to stop) to deprive targeted people of their constitutional right to vote (e.g., by purging them from the voter rolls right before the election), or make it so difficult (e.g., engineering 6-hour lines in Democratic districts, thus requiring losing a day’s pay to vote) that they may decide not to vote, or may not be able to afford the time off that is required.
The GOP’s actions are effectively attempting to return as much as possible to the days when only white property owners (i.e., the ones not targeted by GOP voter suppression) got to vote, but of course they won’t admit it. Just like they are not honest about the Ryan budget killing Medicare as a health insurance program. Instead of supporting policies that the majority of the people support (e.g., Medicare), they try to win by keeping the other side from voting.
It is telling that when the courts make rulings to protect people’s constitutional right to vote, that the headlines (e.g., this week’s headlines on the ruling against North Carolina) are “Court rules against GOP” or “Court rules for Democratic Party” rather than “Court rules for democracy and the Constitution”.
Our country has been moving steadily towards more democracy (e.g., the 15th and 17th amendments to the constitution), and the GOP wants to return to having less democracy.
(2) The FBI has decided they have an entirely different policy for discussing ongoing investigations for Hillary Clinton that they do for every other citizen. They are even coordinating Clinton leaks with Rudi Guliani, while refusing to leak anything about their investigations into Trump/Manifort/Russia.
Democracy needs all of us to trust our federal courts and law enforcement officials. At least the IRS values their role and reputation, and does not leak Trump’s tax returns.