What expectations have you placed on yourself?
The Pygmalion Effect describes how we literally perform at the level that people expect us to. This has played out with very damaging consequences in sociological experiments related to our identities (age, race, gender) and in turn impacted our careers. In one study, teachers were told that certain students (randomly assigned) would experience significant growth that year. The teachers were also instructed not to give these students special treatment. The result was that the students, in fact, did outperform their peers.
This has a pretty profound impact on how others can impose limitations, or extend the potential, of our lives. We also self-impose a pygmalion effect. Whatever assumptions you have about your own performance .... "I'm too old." "I'm not good at technical stuff" "It's mostly men doing that work" "I'm not a creative" ... realize that these thoughts are a bigger impediment to your career progress than anything 'real'. Name it, tame it, reframe it.