It is dark. You can't see. You are disorientated.
Confusion and panic set in.
You trip over the cat, bang against your scope and drop the eyepieces.
When you get your telescope use it first during the day. And practice with it. Try to learn which knobs are which and how to move it so that it points in different parts of the sky. If you have a Newtonian try rotating the tube so that the eyepiece is in a completely different position - maybe learn to do the Meridian flip - gawd, what's that!
If this all sounds a bit trite and extreme, believe you me, if you are not used to operating in the dark the first time you try it will not be easy. Fortunately, or unfortunately depending on your point of view, the chances are the when you get your first scope the skies will be cloudy so you won't be able to see anything. So if it isn't raining take the opportunity to set it up where you intend to use it, level the site out if you can and mark the position of north - use a compass or maybe Google Earth.
If, for some reason, you haven't got a manual then go online and download one - and read it even if a lot of it doesn't make much sense first time round - it will, eventually. Like any new subject there are a lot of terms which sound completely alien at first sight - Eye Relief? Some kind of eye drop? Exit Pupil? A naughty child?
With Newtonians you will have to put it together in the correct order and balance it. Once you have done this mark the tube in some way so that you know where to put the clamps when you next use it. Except, of course, when you add further objects like a camera which upsets the balance. But that is for the future.
With Equatorial Mounts you need to orientate it according to your latitude - again, use Google Earth. And not too difficult to do once you have worked out which knob to turn and which dial to read. However, do make sure it is securely clamped in position when you finish otherwise the whole mount can move and the scope may think it is somewhere in the Artic circle - this happened to me twice and I couldn't understand why I couldn't find or track anything until the following day when I could see what the problem was.
The positions of the declination and right ascension knobs are another source of difficulty when operating at night - I still have difficulty with my Refractor which seems to have them in a totally different position to my Reflector. Maybe mark them in some way so that you can find them.
But of course, before doing any viewing you have to align your finderscope. So you set the scope up and insert the finderscope. If it is a zero magnification red dot and you try to do this during the day you will probably find it very difficult to see the actual red dot. And it is quite important that you focus on something as far away as possible, otherwise however carefully you centre the object, there will be some parallax error which will show up when you try to find stars which are very, very far away.
If you have a finderscope - a small telescope - and it has cross hairs then it is much easier to do the alignment. But in both cases the procedure is the same. Start off with the 25mm eyepiece, centre it in scope, then go to the finderscope or red dot and adjust the side and top knobs until it is centered. Then, if you have a higher magnification 10mm eyepiece, switch to that and see if you are still centered in both the finderscope and the main scope. If you are unlucky, as I was with my first red dot finder, you may not have sufficient side adjustment to properly centre anything - ask for a replacement! And finally, if you can be patient, when you do get your first chance to view the night sky, choose a bright star and check this alignment again. Don't use the Moon as it is too large.
The more accurate the finderscope alignment the easier it is to find anything.
Then there are the eyepieces. You start off with the 25mm and find the Moon, or maybe Jupiter or Saturn. Wow! Ok, let's switch to the high magnification 10mm eyepiece. You fumble around and disturb the scope so that by the time you eventually get the 10mm in position you have completely lost the object of your affections. Don't worry, with practice you will do it perfectly.
Setting Circles: Are they a gimmick or not? Certainly with my Skywatcher 130 Reflector you needed at least 3 hands to do anything with them, plus the fact that their positions made it very difficult to actually read them. And of course the accuracy of the dials is only to 1 degree and preclude any real accuracy in setting anything. Others may disagree and the orientation on other scopes may be much better, but for beginners I really think they are best ignored.
These are just a few comments which I hope will be useful, the final one being
Read, be Patient and Practice