I feel the Holy Spirit, as the third person of the Trinity, is often overlooked.
Kinda like the third tenor…right?
We can blame it on Scripture. We can say we couldn’t properly cross-reference "Advocate" (John 16:7), "Helper" (John 14:16 [NASB]), or the abbreviated "Spirit" (Isaiah 11:2) with the "Holy Spirit".
"There are just so many names in the Bible…!"
We can blame it on the overwhelming, but nonetheless diverting, bounty of blessings received when accepting Jesus Christ as our Savior (Ephesians 1:3-14): eternal life, brotherhood with Jesus, reconciliation with the Father, irrevocable salvation, a Heavenly mansion…and last but not least, the Holy Spirit.
I have to admit that "eternal life" and "having Jesus as a bro" are pretty hard acts to follow.
But in the final analysis, we can only blame ourselves for slighting the Holy Spirit as we routinely suppress the Spirit in favor of self-centeredness, self-esteem, and self-service.
Which is to say we tend to desire ourselves more than God.
And in seeking self and neglecting the Spirit, we bring burden and displeasure on ourselves that was neither necessary nor intended.