Filippo Brunelleschi was a passionate but patient artist who was willing to withstand criticism within committee meetings and frequent modifications from political decisions in order to get his design put into practice. He would call on all of his skills in order to ensure that the final construction was faithful to his designs, including inventing several items of machinery for the purposes of construction of the dome.
The greatest technical challenge to Brunelleschi was to create and implement a design that would cope with what had gone before and produce something that would overcome the lack of future planning delivered in the earlier versions of the cathedral. No blame can really be laid at the door of architects a century before who simply did not have the knowledge at that time over planning features this large and considerations of some of the physical impacts that would result from that.
The Florence Cathedral is clearly not the only religious building that has been developed over generations, even over centuries, where a cycle of artists have had to adapt to what had gone before and implement their own ideas within the constraints of what is possible considering the status quo. This can lead to issues with not just technical challenges but also just ensuring stylistic consistency. As a general rule, artists take huge pride in their work and do not cope well with any sort of interference from exterior bodies.
Thankfully, Brunelleschi was an intelligent and versatile personality who was absorbed into the committees of Florence local governance and had quickly learnt that patience and flexibility was key to success as an artist in this republic. Defending his work to appointed assemblies was something that this artist was willing to undergo inorder to achieve the various commissions from public bodies that truly lifted his reputation to levels that he would only ever have dreamed of when first taking on his training as a goldsmith.