Another possible reason Trump is refusing to acknowledge defeat could be that he is trying to set himself up with the leverage to extort Joe Biden into giving him some accommodations.
Yesterday I posted an article suggesting, based on conversations with Greg Palast, Thom Hartmann and Jonathan Simon, and an article by David that Trump and the Republicans are colluding to run out the clock, not necessarily win the lawsuits, so as to block finalization of the electoral college count so the election will be thrown into the House of Representatives, where Trump would win. It's called an article 2, 12th Amendment gambit. I referenced the election of 1876, in which Rutherford Hayes, though he lost both the popular and electoral college vote, became president instead of Samuel Tilden. One commenter of the article on Dailykos came up with three links that argue that this theory is highly unlikely.
I'm not sure that totally rules out the possibility that this is what Trump is trying to do, but it has unleashed my imagination to consider other possibilities.
One thing I learned about the 1876 election between Hayes and Tilden was that the Republicans basically blackmailed the Democrats. They made a deal that in exchange for letting Hayes win, the Republicans would do certain things, as this wikipedia excerpt describes:
"During intense closed-door meetings, Democratic leaders agreed reluctantly to accept Hayes as president in return for the withdrawal of federal troops from the last two still-occupied Southern states, South Carolina and Louisiana. Republican leaders in return agreed on a number of handouts and entitlements, including Federal subsidies for a transcontinental railroad line through the South. Although some of these promises were not kept, in particular the railroad proposal, it was enough for the time being to avert a dangerous standoff."
Now, the links above suggest that it is unlikely that Trump can succeed in an article 2, 12th Amendment gambit. He may still try it with his Supreme Court leverage. But another possibility is he is looking at the deal that was made in 1876. He may be trying to create leverage so he can cut a deal with the incoming Biden-Harris administration. Probably first on his priority list would be to be pardoned in advance for anything remotely criminal that is uncovered. Once he leaves office it will be possible for Biden to order deep investigations of all of Trump's actions, orders and connections. It would be a miracle if he doesn't get busted many times over for illegal and corrupt actions and orders.
Since it is unlikely that he can pardon himself, he may be trying to build the leverage to demand that Biden give him what Obama gave Bush, a pass on investigating him. I surely hope that if Trump tries that, Biden will tell him to stuff it. If Biden agrees to it, we need to take to the streets. And keep in mind that the promises the Republicans made to persuade the Democrats to allow Hayes to snatch the victory away from Tilden were NOT KEPT.
Even if Biden does make a deal with Trump he can always say that the deal was made under duress and then actually start the charges against Trump with one for extortion.