I live I the US (so I'll speak to that situation), where it certainly is difficult to influence who is on the ballot for the major parties, but we do pretty much have open ballot access, where anyone that follows the process can stand for an election, and write in votes are at least very widely accepted.
the likelihood of a write-in candidate are small. i could not find any actual statistics but this article which points out that write-in candidates do win occasionaly:
but the article also shows that some write-in wins are based on a technicality, like when there are more seats than nominated candidates.
in other words, this is not a level playing field. write-in candidates are not on equal footing with candidates nominated by established parties. even alternative parties usually have little chance.
in a truly democratic system write-in candidates would have an equal chance to get elected compared to those nominated by major parties. i don't know what the solution here is. in the current systems, those with more funds can do more campaigning. so do we need to eliminate campaigning entirely?
likeability and eg integrity of character are much better indicators of a good candidate than the amount of money they can spend to get their name promoted.
equal chance refers to the awareness and knowledge about each candidate among the voting population. that can be achieved by promoting all candidates equally.
for other qualities, we need to get a better understanding what makes good candidates, and educate voters to choose candidates based on that.
