With hindsight it does seem like an unnecessary election.
You are really trying desperately to put a gloss on this, aren't you Julie 8008?
Gordon Brown was certainly criticised for dithering and not going for an immediate GE. This was before the Fixed Term Parliament Act, so had much more latitude in this respect. Or so it was believed, when it was thought that the Fixed Term Parliament Act prevented calling elections on the basis of opportunism. Then May called the election and found that the Opposition did not obstruct the dissolution of Parliament. Now the FTPA seems a bit of a nonsense, but that wasn't known until it was tested.
Theresa May herself said at least six times that she would not call an election. She did so wasting time and money. She had called the election only a couple of weeks after despatching the A50 notification to Brussels, when the clock had started ticking on the two years. It was still the time of the 'Brexit means Brexit and I intend to make a success of it' and the 'Red, White and Blue Brexit. There was no talk at the time about being 'in the middle of negotiations' or a 'transitional period', and it was all supposedly going to be done and dusted within the time period.
Would she have been damned if she didn't if she had waited until the 5 years were up? I doubt it. That would have been playing by the rules - but mighty inconvenient for the Tories because if they hadn't got a good Brexit deal, the election would have come just as things were shown to not be going well.
IMO it was done wholly to serve the interests of the Tory party - she believed the polls talking about a 100 seat majority, which would have been a wonderful opportunity to stick it to the Labour party, (who had by no means covered themselves in glory the previous summer with their botched attempt to rid themselves of Corbyn as a leader). We then had some piffle from May about her sensing the country was behind her, but the Opposition wasn't. In that, she completely misread the situation, the Opposition (the clue should be in the name) fell in meekly behind her in the main, but the Country said words to the effect of 'Wait a minute, we are not sure of your vision for Brexit, although we don't quite know what we want'. Not that this bothered her, she still blundered on but stitched up a deal with the DUP.
What a turn around! I shouldn't be too harsh - it enabled my constituency to boot out a Tory MP, three years sooner than we expected to have the opportunity. Bear in mind that in more than 45 years of voting, I have only once voted Labour, but I for one was utterly sick of the constant criticism which Corbyn was getting. I wonder how many other people thought like me?