Might be because he's afraid he may not be able to recall what his latest position on some given issue is. And then be called out on it with video or audio. He changes his positions every couple of weeks it seems.
Well Trumps not quick witted enough when it comes to the issues themselves for that very reason....However, it doesn’t bother Trump in the slightest, (as long as it’s not one on on), even when he’s called out....he just goes into his ‘fantasy spin zone’ and pulls in his followers more than willing to take the ride with him. But he can’t sustain that for much longer as he’s got defectors already.