When you ride with the fastest riders it may be difficult enough for you to just stay with the group. If that is the case, there will not be any opportunity for you to make early, serious attacks before you increase your VO2max and threshold.When you get a larger aerobic engine you will realize whether it was the insufficient VO2max/threshold that was the problem or insufficient anaerobic power. VO2max also plays a major role in the minutes where the attacks start. It may also be the factor which ensures a successful break.
2) Insufficient anaerobic power/sprint
When you ride with the fastest riders it might be difficult enough for you to just stay with the group. If that is the case there will not be any opportunity for you to make serious attacks from the distance before you increase your VO2max and threshold. When you get a larger aerobic engine you will realize whether it was the insufficient VO2max/threshold that was the problem or that the problem was insufficient anaerobic power. VO2max also plays a major role in the minutes where the attacks go on and is single quality that might be the difference to make a successful break.If you feel comfortable during the race, just waiting for the moment to attack, then unsuccessful attacks might be caused by insufficient anaerobic power/sprint. What happens is that the whole bunch reacts when you start to jump and catch you quickly because there is not enough punch in your jump. Also the other riders may be extraordinary aware of your attacks since you have showed that it’s not a problem for you to stay in the group.
3) Tactical mistakes
Separating yourself from a group is difficult, because you are competing with riders at your own level and they dream of winning the race. Thus, they are not going to just let you make a solo ride without hunting you to the finish line.
If you are not significantly stronger than your opponents (that is actually quite normal) then you will have to use your mind to make a clever move. Instead of making power-attacks then try making a slow attack that the other riders won’t pay attention. What the other riders might think is “he looks tired and if that is the best he can come up with he will be back in a few minutes. I don’t have to pull him back, he will come by himself. I’ll save my energy for serious attacks…”And that is exactly the point: You get a gap for free and the bunch doesn’t react (in time) because you didn’t frighten them with a scary power attack. An extra benefit is that you don’t have to make an anaerobic burst to make the gap what gives you a better chance to find a decent pacing strategy.