When you understand photography and your camera intimately, you are more likely to get the photographs you want. Newcomers to photography are often disappointed by their results because the excitement provided by the subject has a tendency to override what they are actually seeing in the viewfinder. If you do not have a clear understanding of the three elements of exposure, a knowledge of basic composition and an appreciation for light, or an understanding of focus and depth of field, an image can fail.
Disappointment in an image can also lead to you to conclude that you need a better camera and lenses take better pictures. In certain circumstances they can: edge-to-edge sharpness, image noise, and shallow depth of field are all factors that quality equipment can improve on, but they are not required for all images to be successful. The essentials of what makes an image great, such as composition, ‘correct’ exposure, attention to light and details…all these are the work of the photographer alone, dependent on the choices the photographer makes. Even an entry level DSLR gives you all the controls you need, the rest depends on you.
Later, when basic techniques and camera use are understood, the next stage may be to develop the necessary visual literacy to understand what makes a good photograph. Learning the difference between a photograph of a beautiful subject and a beautiful photograph of a subject becomes pertinent.
Finally, if you are unsatisfied with the results because they do not meet your first expectations, give them some time before deleting them. Sometimes a contrasty image may look better in B&W, or a uniformly textured image which may look dull by itself, could be a great image for layering with another. Sometimes simple cropping can do wonders. Looking at your images a second time, without any preconceived notions, may reveal a gem!