No one else has the guts to form a third party?
Both parties are corrupt, but
BNP is definitely better than the Awami League.
However the Awami League is a far older party and has far more supporters than the BNP partly because it is older.
Even for example the Awami League's presence abroad is far stronger than the BNP's, they are in the UK, USA, Canada, Italy, France etc.
When I say the Awami League has far more supporters I do not mean most ordinary Bangladeshis like them. Most ordinary Bangladeshis do not care about either party and just want to feed their families. However AL has far more hardcore supporters and party-walas than the BNP does.
The Awami League however are far more violent, brutal and ruthless partly because of their tradition of student "activism" (thuggery) which dates from the time of former Pakistan Muslim student strongman Mujib (who worked for an independent Muslim homeland of Pakistan).
The Awami League also has the support of Bangladesh's biggest Muslim group, Tableeghi Jamat (biggest Muslim group in the world). Mujib donated the land for the annual Tableeghi gathering in Dhaka, the biggest Muslim gathering on earth.
In addition to the BNP and BAL, there is Jamat (who like Jamat in Pakistan do not get that many votes) and the Jatiya party of ex-president Ershad.
Bangladeshis have long pined for an end to Hasina and Khaleda and even coined a term for this, called "Minus two".
During the caretaker government period the military-backed administration wanted Mohammed Yunus to form a party, which he did. The gentle, perhaps naive, and somewhat weak and timid Yunus quickly ended this project once he was the target of mudslinging, campaign of black propaganda i.e. standard politics which the inexperienced and quiet Yunus couldn't handle.
If a major national third party were to be formed they would immediately be targeted by both the Awami League and the BNP, which are in essence two mafia organizations - political parties, as both high level Awami-walas and BNP-walas are in politics to make money.
Imran Khan in Pakistan has served as a good example of how a completely new party can be started and gain strength.
The good news however is though the Awami League and BNP still dominate Bangladeshi politics, due to the growth of the media, social media and economic growth they are being tamed gradually and slowly slowly starting to behave more responsibly.
Hasina's current administration though bad is far better than her previous reign in power and she has been comparatively more civilized and responsible. There are some good non-corrupt people in her party e.g foreign minister Dipu Moni, education minister Nahid and finance minister Nahid.
Bangladesh has had the 5th highest rate of economic growth in the world from 2008 (if we count 2008 to now as one period) so overall things are generally ok.
Everyone knows in 12 months time Hasina will be out and Khaleda will be in.