Should you compare your successes to others? If you're "doing better" than someone, does that make you feel better? Or if you aren't progressing as far as those around you does it kill your motivation?
STOP. Just STOP.
What others are doing is their business, and what you are doing is your business. To compare yourself to others is simply impossible... they may have a different starting point than you, they may have different goals than you, they may have different measures of success than you. Too often we feel that if we're standing next to someone beautiful that we aren't beautiful anymore, or that if we are standing next to someone very thin then suddenly we feel fat.
Rather than comparing yourself to others, start comparing yourself to yourself. What's awesome about you? What are your favorite qualities about you?
I have people participate in challenges regularly to help improve their health, nutrition, fitness and wellness. Sure,that's the start of their journey and the initial reason why they join a challenge group, but as they progress their feeling success evolved from an outer result to an inner results.
Here are some scale and non-scale victories from some of my former challengers:
Stopped taking three fast acting diabetes shots each day to just one
Increased number of push-ups before dropping to knees from 16 to 25.
Being able to run again after recovering from a knee-injury
Ability to touch ones toes when they couldn't at the beginning of the challenge
Going from feeling like they "should" workout to feeling like they WANT to workout
As you can see, each of these challengers had completely different circumstances and completely different goals. How can they even compare themselves to each other? It's impossible and just not fair to themselves.
Stop robbing yourself of joy and comparing yourself to others. Start empowering yourself and recognizing your ability to grow, improve or even be content with just being.