Former Labour MSP Monica Lennon says voters could not get beyond Keir Starmer's unpopularity.
Scottish Labour leader Anas Sarwar says he is "proud" of his work with Sir Keir Starmer after the prime minister announced he would resign.
The Scottish Labour leader was the first major party figure to call for the prime minister to quit.
Kemi Badenoch hailed the Scottish Conservatives' first by-election win since 1973, after the party took Aberdeen South from the SNP.
The Conservatives secured a comfortable victory over the SNP in Aberdeen South after throwing everything at the seat.
The Tories take Aberdeen South, while the SNP wins in Arbroath and Broughty Ferry.
Sir Keir Starmer says the Scottish secretary "acted appropriately" despite an "administrative oversight".
The SNP leader is to be formally sworn in on Wednesday before he chooses a new cabinet.
The post-mortem has begun among Scottish Labour but can anything be done to turn the party's fortunes around?
