In most modern steampunk settings you see rudimentary use of electricity (a good example is Dishonored) however, no one seems to be too interested in advancing electric technology beyond very crude applications like electromagnets, Tesla coils and the occasional light bulb.
Obviously this is necessary for storytelling, to create a futuristic steampunk society.
What are the possible justifications for the continued relevance of steampower over electricity?
So rather than choosing one answer I think I'll do an edit to summarize some of the great thoughts in this (?)thread.
"Steampunk done right" - @TCAT117
This answer definitely raises some very good points, I and probably many others have not yet considered. As such it is very helpful to completely flesh out the society in a steampunk world. However I don't feel, the initial question, of how can a steampunk world "realisticaly" exist (and more importantly persist) despite the knowledge (and use) of electricity, is answered here. Furthermore this description presumes that there cannot be societal change in a steampunk world. (Treasure Planet and Wild Wild West are both broadly considered Steampunk and neither would I necessarily attribute with "victorian").
Overall I think this is an interesting take on Steampunk, but definitely not the only "valid" one.
"The AC Generator was never invented" - @Magus
This is a deceptively simple, yet effective idea. The repercussions of not having AC-technology are incredibly far reaching and would serve perfectly for preventing centralised distribution of electric energy.
"Conspiracy" - @Willk
I had thought about a solution similar to this: Cultism. The problem with this solution is, that it is unbelievable to persist over centuries. I think this would work very well in a story about societal trumoil and technological advancement.
"Money and Law" - @StephenG
Similar to Conspiracy and Cultism, this doesn't prevent technological advancement indefinitely, but would make for a great story about revolution and change.
Fuel Shortage - @TheShadowOfZama
Another extremely small change to the world with incredible effects on the developement of technology. Extreme shortage (or complete lack) of (fossil) oil, would not only set back combustion engines, but also prevent the invention of classic plastics and many medicines.