Bangladesh is a young democracy. All democracies go through this phase where politicians find loopholes in the system to manipulate the elections. Good political parties then try to plug these loopholes. Even in the world's oldest democracy political parties still go to the court to try and overturn elections results alleging fraud (see - A sampling of recent election fraud cases from across the United States). In India (the world's largest democracy) too, booth capturing and ballot stuffing was once common. Even in Australia, electoral frauds were common enough that laws had to be made to counter it but some Australian political parties still allege that electoral frauds happen even today.
The evolution of democratic values totally depends on the political leadership.
Mrs. Shiek Hasina is an admirer of the former Prime Minister of India Mrs. Indira Gandhi, a staunch democrat who too had an authoritarian tendency when she entered politics and struggled.
... Ms. Hasina said: “We had nowhere to go at that time [after the massacre of her family in 1975]. Our government did not allow us to return to our homeland. It was Indira Gandhi who gave us shelter. We took political asylum and stayed in Delhi for six years. She was truly like our mother.” - The Hindu, January 12, 2010
Hence it is not far fetched to believe Mrs. Hasina draws inspiration from Mrs. Indira Gandhi's style of politics, while trying to figure out her own unique path.
Like her inspiring father, the current Prime Minister of Bangladesh does believe in democracy. But she also understands the reality of Bangladesh politics:
Political violence is a fact there - her father, a hugely popular leader, was assassinated and 18 members of her family, including her 10-year-old brother, and relatives were massacred. She had to seek refuge abroad to survive.
Bangladesh has also seen many military coups.
Some opposition parties of Bangladesh are backed by the military.
Some lean towards religious fundamentalism.
Foreign powers - USA (and other western countries acting in cohort with the US), China and India - often interfere in Bangladesh's internal affairs.
It's really tough to navigate such hurdles to become a good democracy. (Just look at India for a great example - it was a flourishing democracy that today is struggling under electoral autocracy because Modi and his organisation are deliberately damaging the democratic institutions to be in power).
Mrs. Hasina is the daughter of Sheikh Mujibur Rahman, the founding father of Bangladesh, and has imbibed her father's political values. She has lived abroad in democratic countries, in both the west and the east, and understands it well. All these factors, along with her undeniable popularity with the masses currently makes her the best option that Bangladesh politics has to slowly evolve into a true and fair democracy.
Both Bangladesh and Mrs. Hasina need time to evolve.