Would you build a house without blue prints? I hope not. But I see something similar on almost a daily basis. As a personal trainer I meet people all of the time who have all but given up on getting in shape. They spend several hours a week at the gym for months, but it's still not happening for them. A lot of them have tried almost everything but have never gotten the results they wanted. It's not because they didn't work hard or weren't committed. Of course nutrition plays a huge part, but there is more to it than that. The fact is the majority of these folks never had a structured plan to begin with. A fitness program without structure is like building a house without blueprints. You have no way of knowing how it is going to turn out. If you want specific results or goals to be met in your fitness program you need specifics to begin with. Whether you want to get stronger, lose weight or make it to the Olympics you have to have a plan. You need to train.
Training involves specific, predetermined goals, measured results within a set time frame and an individualized plan to achieve them. Any other strategy is simply haphazard. With general exercise your results will be general. When you train there is a specific purpose. You don't need a personal trainer or coach to train, but a good one can help you expedite the process.
If you are hitting the gym on a regular basis and are not seeing the progress you want, take an honest look at what you are doing. If there are no specifics or a clear cut objective, put pen to paper and define your short term and long term goals. They should be realistic and timely. Next, put a structured plan into place to achieve your objective. The good news is that there are hundreds of legitimate training templates already available via the internet for whatever you may want. Start with an 8 or 12 week program and document your sessions and progress. Sets, reps, weights used - write it down! With defined goals, a structured plan and commitment, you'll get the changes you want. If you want specifics in your fitness program define them and start training.